Display apparatus, display method, program and recording medium

ABSTRACT

A display apparatus, which makes one pixel displayable in four colors, that is, three primary colors and a white color, and inputs and displays chrominance signals corresponding to a mixing ratio of the four colors, includes a color correction instrument which performs first color correction of increasing the saturation of chrominance signals, and a second color correction of decreasing at least the saturation of the chrominance signals, when a predetermined color component exists in the chrominance signals corresponding to a pixel, selection instrument which switches temporally and selects either of first chrominance signals obtained by the first color correction, and second chrominance signals obtained by the second color correction, and a display instrument which displays the chrominance signals, which are selected, in the pixel.

This application is a U.S. national phase application of PCTInternational Application PCT/JP2004/016126 dated Oct. 29, 2004.

TECHNICAL FIELD

The present invention relates to a display apparatus, a display method,a program, and a recording medium for making one pixel displayable infour colors, that is, three primary colors and a white color, andinputting and displaying chrominance signals corresponding to a mixingratio of the above-mentioned four colors.

BACKGROUND ART

CRT, LCD (Liquid Crystal Device), DLP (Digital Light Processing Device),PDP, and the like are used as devices for color display, and RGB (red,green, and blue) three primary colors are used as general fundamentalcolors. On the other hand, white is also added in a part of LCD displaysand DLP projectors to emphasize brightness.

That is, a display apparatus in which one pixel can display the color offour colors of R (red), G (green), B (blue), and W (white), and whichdisplays RGB signals, which are inputted, by mixing the color of thesefour colors is used (e.g., refer to Japanese Patent Laid-Open No.5-241551, and A. Kunzman and G. Pettitt, “White Enhancement forColor-Sequential DLP”, SID International Symposium Digest of TechnicalPapers, USA, SID (Society for Information Display), May, 1998, Vol 29,pp. 121-124). A display apparatus which displays one pixel in the colorof four colors of RGBW in this way is used, for example in a direct-viewliquid crystal display apparatus, a DLP projector, or the like. Forexample, a four-color wheel of RGBW is used in a field-sequential systemof one-chip DLP data projector which uses a color wheel. In addition,four display elements, which can display four colors of RGBW, per pixelare used in a liquid crystal display apparatus.

By displaying each pixel not only using RGB but using W, in comparisonwith the case of displaying only by RGB, it is possible to performbright display, to increase contrast, and to reduce the consumed powerof a lamp when brightness is same.

The structure of such a conventional display apparatus 51 is shown inFIG. 28.

The display apparatus 51 is constituted of white color componentdetection instrument 7, white display element driving instrument 8, awhite display unit 9, RGB display element driving instrument 10, and anRGB display unit 11.

The white color component detection instrument 7 is the instrument whichdetects a white color component from RGB signals inputted.

The white display element driving instrument 8 is the instrument whichdrives the white display unit 9 in order to display a white colorcomponent detected by the white color component detection instrument 7.

The white display unit 9 is the instrument which displays a white colorcomponent by being driven by the white display element drivinginstrument 8.

The RGB display element driving instrument 10 is the instrument whichdrives the RGB display unit 11 in order to display the RGB signalsinputted.

The RGB display unit 11 is the instrument which displays RGB componentsby being driven by the RGB display element driving instrument 10.

Screen structure in the case that the display apparatus 51 is a liquidcrystal display apparatus is shown in FIG. 29. Reference numeral 52denotes a basic unit which constitutes one pixel, and is constituted offour liquid crystal cells which can independently control the extent oftransmission of white light exposed from the back. Then, the four colorfilters of R, G, B, and W are located to these four liquid crystalcells, respectively. In this way, when the display apparatus 51 is aliquid crystal display apparatus, a screen of the RGB display unit 11and white display unit 9 has structure as shown in FIG. 29.

In addition, when being a DLP projector, the display apparatus 51 hasthe structure that four colors of RGBW are time-sequentially switchedand is displayed in one pixel of the screen while synchronizing with acolor wheel. Thus, when the display apparatus 51 is a DLP projector, theRGB display unit 11 and white display unit 9 are constituted of thecolor wheel, DMD (Digital Micromirror Device), and the like.

Next, the operation of such the conventional display apparatus 51 willbe explained.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 51, such as a personal computer, DVD equipment, ora TV receiver are inputted into the RGB display element drivinginstrument 10 and white color component detection instrument 7.

The RGB display element driving instrument 10 generates drive signals ofthe RGB display unit 11 in order to display the RGB signals inputted,and drives the RGB display unit 11 with the drive signals.

On the other hand, the white color component detection instrument 7detects a white color component from the RGB signals inputted, andoutputs the white color component to the white display element drivinginstrument 8. The white display element driving instrument 8 generates adrive signal of the white display unit 9 in order to display the whitecolor component from white color component detection instrument 7, anddrives the white display unit 9 with the drive signal.

The RGB display unit 11 displays three colors of R, G, and B by beingdriven by the RGB display element driving instrument 10. On the otherhand, the white display unit 9 displays one color of W by being drivenby the white display element driving instrument 8.

Since the white by the white display unit 9 is added to the white by theRGB display unit 11 in the display apparatus 51, brightness becomesnearly twice in comparison with the case of only the RGB display unit11.

In this way, the display apparatus 51 can achieve the display of a fullcolor image whose brightness and contrast are increased by four colorsof the three primary RGB colors and white color.

Nevertheless, in the display apparatus 51, a luminance ratio of white toRGB becomes nearly two times as large also using the white display unit9 in compared with the case of only the RGB display unit 11. Inconsequence, the difference in brightness between white and normal colormay become so large that, it may be apart from the sense of brightnesswhich the brain stores, and sense of incongruity may be felt as to theway those colors appear. Thus, the brightness of image portions ofcolors other than white becomes dark relatively in comparison with thebrightness of a white portion. As a result, since the brightness of somecolors is much different from that of a white portion, the colors appeardifferently, and hence, sense of incongruity arises.

Since the luminance ratio of white and bright yellow becomes large inparticular, yellow looks darker and the difference from the memory colorof yellow becomes large, and hence, the sense of incongruity becomeslarge. Thus, as shown in FIG. 30, when pixels 14 in pastel yellow whichare bright yellow, and pixels 13 in white which are white are displayedon the display screen, the bright yellow looks darker due to thecontract with the white and the bright yellow may appear greenish. Suchthe sense of incongruity arises similarly also in bright cyan or brightmagenta.

Thus, a display apparatus in which one pixel can be displayed in thecolor of four colors, that is, the three primary colors and a whitecolor, and which inputs and displays chrominance signals correspondingto the mixing ratio of the color of the four colors has a problem thatthe brightness of colors may be apart from those which a brain storeswhen the difference in brightness between white and normal colorsbecomes large, and the sense of incongruity may be felt as to the waynormal colors appear.

DISCLOSURE OF THE INVENTION

The present invention aims at providing a display apparatus, a displaymethod, a program, and a recording medium capable of decreasing thesense of incongruity of the visual aspect of color in consideration ofthe above-mentioned problem.

In order to solve the problem mentioned above, the first aspect of thepresent invention is a display apparatus which makes one pixeldisplayable in four colors, that is, three primary colors and a whitecolor, and inputs and displays chrominance signals corresponding to amixing ratio of said four colors, comprising:

color correction instrument which performs a first color correction ofincreasing the saturation of said chrominance signals and a second colorcorrection of increasing a white color component of said chrominancesignals, when a predetermined color component exists in said chrominancesignals corresponding to said pixel;

selection instrument which switches temporally a first chrominancesignal obtained by said first color correction, and a second chrominancesignal obtained by said second color correction, and selects either; and

display instrument which displays the chrominance signal, which isselected, in said pixel.

In addition, the second aspect of the present invention is a displayapparatus which makes one pixel displayable in four colors, that is,three primary colors and a white color, inputs chrominance signalscorresponding to a mixing ratio of said four colors, and displays themwithout decreasing the number of colors, comprising:

color correction instrument which performs a first color correction ofincreasing saturation of said chrominance signals and a second colorcorrection of increasing a white color component of said chrominancesignals, when a predetermined color component exists in said chrominancesignals corresponding to said pixel;

height generation instrument which gives, when there is a region where aplurality of pixels having said predetermined color component existadjacently, at least height difference in saturation to said region byselecting either of said first chrominance signals and said secondchrominance signals for every pixel of said region according to apredetermined pattern for selecting said first chrominance signalsobtained by said first color correction, and said second chrominancesignals obtained by said second color correction in turn for every onepixel or a plurality of adjacent pixels; and

display instrument which displays said region where at least said heightdifference in saturation is given.

In addition, the third aspect of the present invention is the displayapparatus according to the first or the second aspect of the presentinvention, wherein said predetermined color is yellow, magenta, or cyan.

In addition, the fourth aspect of the present invention is the displayapparatus according to the first or the second aspect of the presentinvention, wherein said three primary colors are red, green, and blue.

In addition, the fifth aspect of the present invention is the displayapparatus according to the first or the second aspect of the presentinvention, wherein said chrominance signals are RGB signals.

In addition, the sixth aspect of the present invention is the displayapparatus according to the fifth aspect of the present invention,wherein,

when said predetermined color is yellow, said color correctioninstrument performs said first color correction by decreasing a value ofa B signal of said chrominance signals and performs said second colorcorrection by increasing a B signal of said chrominance signals, when ayellow color component exists in said chrominance signals correspondingto said pixel.

In addition, the seventh present invention is the display apparatusaccording to the first aspect of the present invention wherein saidselection instrument switches temporally and selects either said firstchrominance signal or said second chrominance signal using a signal ofdetermining the timing when said display instrument performs display insaid pixel.

In addition, the eighth aspect of the present invention is the displayapparatus according to the second aspect of the present invention,wherein said height generation instrument performs the selection of saidfirst chrominance signals and said second chrominance signals using asignal of determining timing when said display instrument performsdisplay in said pixel.

Furthermore, the ninth aspect of the present invention is a displaymethod of making one pixel displayable in four colors, that is, threeprimary colors and a white color, and inputting and displayingchrominance signals corresponding to a mixing ratio of said four colors,comprising:

a color correction step of performing a first color correction ofincreasing the saturation of said chrominance signals and a second colorcorrection of increasing a white color component of said chrominancesignals, when a predetermined color component exists in said chrominancesignals corresponding to said pixel;

a selection step of switching temporally a first chrominance signalobtained by said first color correction, and a second chrominance signalobtained by said second color correction, and selecting either; and

a display step of displaying the chrominance signal, which is selected,in said pixel.

Furthermore, the tenth aspect of the present invention is a displaymethod of making one pixel displayable in four colors, that is, threeprimary colors and a white color, and inputting chrominance signalscorresponding to a mixing ratio of said four colors, and displaying themwithout decreasing the number of colors, comprising:

a color correction step of performing a first color correction ofincreasing saturation of said chrominance signals and a second colorcorrection of increasing a white color component of said chrominancesignals, when a predetermined color component exists in said chrominancesignals corresponding to said pixel;

a height generation step of giving, when there is a region where aplurality of pixels having said predetermined color component existadjacently, at least height difference in saturation to said region byselecting either of said first chrominance signals and said secondchrominance signals for every pixel of said region according to apredetermined pattern for selecting said first chrominance signalsobtained by said first color correction, and said second chrominancesignals obtained by said second color correction in turn for every onepixel or a plurality of adjacent pixels; and

a display step of displaying said region where at least the heightdifference in saturation is given.

In addition, the eleventh aspect of the present invention is a programfor making a computer function as color correction instrument whichperforms the first color correction of increasing the saturation of saidchrominance signals and the second color correction of increasing awhite color component of said chrominance signals, when a predeterminedcolor component exists in said chrominance signals corresponding to saidpixel, and

selection instrument which switches temporally a first chrominancesignal obtained by said first color correction, and a second chrominancesignal obtained by said second color correction, and selects either, inthe display apparatus according to the first aspect of the presentinvention.

In addition, the twelfth aspect of the present invention is a programfor making a computer function as:

color correction instrument which performs a first color correction ofincreasing saturation of said chrominance signals and a second colorcorrection of increasing a white color component of said chrominancesignals, when a predetermined color component exists in said chrominancesignals corresponding to said pixel; and

height generation instrument which gives, when there is a region where aplurality of pixels having said predetermined color component existadjacently, at least height difference in saturation to said region byselecting either of said first chrominance signals and said secondchrominance signals for every pixel of said region according to apredetermined pattern for selecting said first chrominance signalsobtained by said first color correction, and said second chrominancesignals obtained by said second color correction in turn for every onepixel or a plurality of adjacent pixels in the display apparatusaccording to the second aspect of the present invention.

In addition, the thirteenth aspect of the present invention is arecording medium which records the program according to the eleventh orthe twelfth aspect of the present invention and can be processed by acomputer.

Moreover, the fourteenth aspect of the present invention is a displayapparatus which makes one pixel displayable in four colors, that is,three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising:

color detection instrument which detects whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

color correction instrument which performs a first color correction ofincreasing the saturation of said chrominance signals and creating afirst chrominance signal, and a second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal,

control instrument which performs the color correction of a chrominancesignal, including said predetermined color component, by said colorcorrection instrument, and performs control so that said firstchrominance signal and said second chrominance signal may be displayedspatially in turn in every predetermined plural pixel units, which arehorizontally and/or vertically adjacent, in said predetermined region;and

display instrument which displays said first chrominance signal, saidsecond chrominance signal, or a chrominance signal, which is not givensaid color correction, in said pixel on the basis of said controlinstrument.

In addition, the fifteenth aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention wherein said every predetermined plural pixel units is everytwo pixel units.

Furthermore, the sixteenth aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention, wherein in the case that said control instrument performscontrol so that said first chrominance signal and said secondchrominance signal may be displayed spatially in turn in everypredetermined plural pixel units, which are horizontally adjacent, insaid predetermined region,

said control instrument switches and selects said first chrominancesignal and said second chrominance signal in every said predeterminedplurality of dot clock signals for determining display timing of everypixel in said predetermined region.

Moreover, the seventeenth aspect of the present invention is the displayapparatus according to the fourteenth aspect of the present invention,wherein in the case that said control instrument performs control sothat said first chrominance signal and said second chrominance signalmay be displayed spatially in turn in every predetermined plural pixelunit, which are vertically adjacent, in said predetermined region,

said control instrument switches and selects said first chrominancesignal and said second chrominance signal for every said predeterminedplurality of horizontal periods in said predetermined region.

In addition, the eighteenth aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention wherein said control instrument performs control so that saidfirst chrominance signal and said second chrominance signal may bedisplayed in a pixel of said predetermined region in turn temporally.

Furthermore, the nineteenth aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention, wherein said control instrument performs control so that achrominance signal which does not include said color component may bedisplayed without performing said color correction, and

performs control so as to be displayed in turn spatially, where it isassumed that all the chrominance signals displayed in a pixel of saidpredetermined region include said predetermined color component.

Moreover, the twentieth aspect of the present invention is the displayapparatus according to the fourteenth aspect of the present invention,wherein said predetermined color component is yellow, magenta, or cyan.

In addition, the twenty-first aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention, wherein said three primary colors are red, green, and blue.

Furthermore, the twenty-second aspect of the present invention is thedisplay apparatus according to the fourteenth aspect of the presentinvention, wherein said chrominance signals are RGB signals.

Moreover, the twenty-third aspect of the present invention is thedisplay apparatus according to the twenty-second aspect of the presentinvention, wherein, when said predetermined color component is yellow,said color correction instrument performs said first color correction bydecreasing a value of a B signal of said chrominance signal and performssaid second color correction by increasing a value of the B signal ofsaid chrominance signal, when a yellow color component exists in saidchrominance signals corresponding to said pixel.

In addition, the twenty-fourth aspect of the present invention is adisplay method using a display apparatus which makes one pixeldisplayable in four colors, that is, three primary colors and a whitecolor, and inputs and displays chrominance signals corresponding to amixing ratio of said four colors, comprising:

a color detection step of detecting whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

a color correction step of performing a first color correction ofincreasing the saturation of said chrominance signals and creating saidfirst chrominance signal, and a second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal,

a control step of performing said color correction of a chrominancesignal, including said predetermined color component, and performingcontrol so that said first chrominance signal and said secondchrominance signal may be displayed spatially in turn in everypredetermined plural pixel units, which are horizontally and/orvertically adjacent, in said predetermined region; and

a display step of displaying said first chrominance signal, said secondchrominance signal, or a chrominance signal which is not given saidcolor correction, in said pixel on the basis of said control.

In addition, the twenty-fifth aspect of the present invention is aprogram for making a computer execute:

a color detection step of detecting whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

a color correction step of performing a first color correction ofincreasing the saturation of said chrominance signals and creating afirst chrominance signal, and a second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal; and

a control step of performing said color correction of a chrominancesignal, including said predetermined color component, and performingcontrol so that said first chrominance signal and said secondchrominance signal may be displayed spatially in turn in everypredetermined plural pixel units, which are horizontally and/orvertically adjacent, in said predetermined region, of the display methodaccording to the twenty-fourth aspect of the present invention.

In addition, the twenty-sixth aspect of the present invention is arecording medium which records the program according to the twenty-fifthaspect of the present invention, and is the recording medium which canbe processed by a computer.

Furthermore, the twenty-seventh aspect of the present invention is adisplay apparatus which makes one pixel displayable in four colors, thatis, three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising:

color detection instrument which detects whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

color correction instrument which performs a first color correction ofincreasing the saturation of said chrominance signals and creating afirst chrominance signal, and a second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal;

judgment instrument which judges whether a plurality of chrominancesignals displayed in a pixel of said predetermined region fulfills apredetermined condition;

control instrument which performs the color correction of chrominancesignals including said predetermined color component by said colorcorrection instrument when not fulfilling said predetermined condition;and

display instrument which displays said first chrominance signal, saidsecond chrominance signal, or a chrominance signal which is not givensaid color correction, in a pixel of said predetermined region on thebasis of said control instrument.

In addition, the twenty-eighth aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said predetermined condition is a condition thatchrominance signals, including said predetermined color component, arenot displayed in two or more adjoining pixels spatially.

Furthermore, the twenty-ninth aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said predetermined condition is a condition that whena chrominance signal which does not include said color component isdisplayed without performing said color correction, and about thechrominance signals including said color component, said firstchrominance signal and said second chrominance signal are displayed inturn spatially in a state that assumes that all the chrominance signalsdisplayed in a pixel of said predetermined region include thepredetermined color component and, either of an area where said firstchrominance signal is displayed, and an area where said secondchrominance signal is displayed is larger by 5% or more than the other.

Moreover, the thirtieth aspect of the present invention is the displayapparatus according to the twenty-seventh aspect of the presentinvention, wherein said predetermined condition is a condition that,when a chrominance signal which does not include said color component isdisplayed without performing said color correction, and concerning achrominance signals which include said color component, said firstchrominance signal and said second chrominance signal are displayed inturn spatially in a state that assumes that all the chrominance signalsdisplayed in a pixel of said predetermined region include thepredetermined color component, either said first chrominance signal orsaid second chrominance signal is displayed except a chrominance signalwhich is not given said color correction.

In addition, the thirty-first aspect of the present invention is thedisplay apparatus according to the twenty-eighth aspect of the presentinvention, wherein, when said predetermined condition is not fulfilled,said control instrument performs control so that said first chrominancesignal and said second chrominance signal may be displayed in turnspatially in every pixel unit or in every plural pixel units in saidpredetermined region.

Furthermore, the thirty-second aspect of the present invention is thedisplay apparatus according to the twenty-ninth or thirtieth aspect ofthe present invention, wherein, when said predetermined condition is notfulfilled, said control instrument performs control so that said firstchrominance signal and said second chrominance signal may be displayedin turn spatially in every pixel unit in said predetermined region in astate that assumes that all the chrominance signals displayed in a pixelof said predetermined region include the predetermined color component.

Moreover, the thirty-third aspect of the present invention is thedisplay apparatus according to the thirty-second aspect of the presentinvention, wherein, when said predetermined condition is fulfilled, saidcontrol instrument performs control so that concerning a chrominancesignal which does not include said color component, said controlinstrument does not perform said color correction, and concerning thechrominance signals which include said color component, said firstchrominance signal and said second chrominance signal may be displayedin turn spatially in every plural pixel units in said predeterminedregion in a state that assumes that all the chrominance signalsdisplayed in a pixel of said predetermined region include thepredetermined color component.

In addition, the thirty-fourth aspect of the present invention is thedisplay apparatus according to the thirty-first aspect of the presentinvention, wherein said control instrument has switching signalgenerating instrument which generates such a switching signal that saidfirst chrominance signal and said second chrominance signal may bedisplayed in turn in every pixel unit or in every plural pixel units,and

wherein performing control so as to be displayed in turn spatially isselecting said first chrominance signal and said second chrominancesignal in turn on the basis of said switching signal.

Furthermore, the thirty-fifth aspect of the present invention is thedisplay apparatus according to the thirty-second aspect of the presentinvention, wherein the control instrument has switching signalgenerating instrument which generates such a switching signal that saidfirst chrominance signal and said second chrominance signal may bedisplayed in turn in every pixel unit, and

wherein performing control so as to be displayed in turn spatially isselecting said first chrominance signal and said second chrominancesignal in turn on the basis of said switching signal, in a state thatassumes that all the chrominance signals displayed in a pixel of saidpredetermined region include the predetermined color component.

Moreover, the thirty-sixth aspect of the present invention is thedisplay apparatus according to the thirty-third aspect of the presentinvention, wherein said control instrument has:

first switching signal generating instrument which generates a firstswitching signal so that said first chrominance signal and said secondchrominance signal may be displayed in turn in every pixel unit in apixel of a predetermined region;

second switching signal generating instrument which generates a secondswitching signal so that said first chrominance signal and said secondchrominance signal may be displayed in turn in every plural pixel unitsin a pixel of a predetermined region; and

switching signal selection instrument which selects said first switchingsignal when said predetermined condition is not fulfilled, and selectssaid second switching signal when said predetermined condition isfulfilled, and

wherein performing control so as to be displayed in turn spatially isselecting said first chrominance signal and said second chrominancesignal in turn on the basis of said first switching signal or saidsecond switching signal, in a state that assumes that all thechrominance signals displayed in a pixel of said predetermined regioninclude the predetermined color component.

In addition, the thirty-seventh aspect of the present invention is thedisplay apparatus according to the thirty-fourth or thirty-fifth aspectof the present invention, wherein said switching signal is a signalusing a signal which determines the timing of said display instrumentwhich displays in said pixel.

Furthermore, the thirty-eighth aspect of the present invention is thedisplay apparatus according to the thirty-sixth aspect of the presentinvention, wherein said first switching signal and said second switchingsignal are signals using a signal which determines the timing of saiddisplay instrument which displays in said pixel.

Moreover, the thirty-ninth aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said control instrument performs control so that saidfirst chrominance signal and said second chrominance signal aredisplayed in a pixel of said predetermined region in turn temporally.

In addition, the fortieth aspect of the present invention is the displayapparatus according to the twenty-seventh aspect of the presentinvention, wherein the color around said predetermined region is white.

Furthermore, the forty-first aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said predetermined color component is yellow,magenta, or cyan.

Moreover, the forty-second aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said three primary colors are red, green, and blue.

In addition, the forty-third aspect of the present invention is thedisplay apparatus according to the twenty-seventh aspect of the presentinvention, wherein said chrominance signals are RGB signals.

Furthermore, the forty-fourth aspect of the present invention is thedisplay apparatus according to the forty-third aspect of the presentinvention, wherein said predetermined color component is yellow; and

wherein said color correction instrument performs said first colorcorrection by decreasing a value of a B signal of said chrominancesignals, and performs said second color correction by increasing a valueof the B signal of said chrominance signals.

Moreover, the forty-fifth aspect of the present invention is a displaymethod using a display apparatus which makes one pixel displayable infour colors, that is, three primary colors and a white color, and inputsand displays chrominance signals corresponding to a mixing ratio of saidfour colors, comprising:

a color detection step of detecting whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

a color correction step of performing a first color correction ofincreasing the saturation of said chrominance signals and creating afirst chrominance signal, and a second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal;

a judgment step of judging whether a plurality of chrominance signalsdisplayed in a pixel of said predetermined region fulfill apredetermined condition;

a control step of performing control so as to perform the colorcorrection of chrominance signals including said predetermined colorcomponent when not fulfilling said predetermined condition; and

a display step of displaying said first chrominance signal, said secondchrominance signal, or a chrominance signal which is not given saidcolor correction, in a pixel of said predetermined region on the basisof said control.

In addition, the forty-sixth aspect of the present invention is aprogram for making a computer execute:

the color detection step of detecting whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in said predetermined region;

the color correction step of performing the first color correction ofincreasing the saturation of said chrominance signals and creating afirst chrominance signal, and the second color correction of increasinga white color component of said chrominance signals and creating asecond chrominance signal;

the judgment step of judging whether a plurality of chrominance signalsdisplayed in a pixel of said predetermined region fulfill apredetermined condition; and

the control step of performing control so as to perform said colorcorrection of chrominance signals including said predetermined colorcomponent when not fulfilling said predetermined condition, of thedisplay method according to the forty-fifth aspect of the presentinvention.

In addition, the forty-seventh aspect of the present invention is arecording medium which records the program according to the forty-sixthaspect of the present invention, and is the recording medium which canbe processed by a computer.

Furthermore, the forty-eighth aspect of the present invention is adisplay apparatus which makes one pixel displayable in four colors, thatis, three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising:

color detection instrument which detects whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

judgment instrument which judges whether a plurality of chrominancesignals displayed in a pixel of said predetermined region fulfill apredetermined condition;

color correction instrument which performs the first color correction ofincreasing the saturation of said predetermined chrominance component ofsaid chrominance signals and creating a first chrominance signal, andthe second color correction of increasing a white color component ofsaid chrominance signals and creating a second chrominance signal;

switching signal generating instrument which generates such a switchingsignal that said first chrominance signal and said second chrominancesignal may be displayed in turn in every one or in plural pixel units,in a state that assumes that all the chrominance signals displayed on apixel of said predetermined region include said predetermined colorcomponent;

first selection instrument which selects said first chrominance signalor said second chrominance signal in turn on the basis of said switchingsignal, in a state that assumes that all the chrominance signalsdisplayed on a pixel of said predetermined region include thepredetermined color component;

second selection instrument which selects said first chrominance signalor said second chrominance signal when said predetermined colorcomponent is included and said predetermined condition is not fulfilled,and otherwise selects a chrominance signal which is not given said colorcorrection; and

display instrument which displays said first chrominance signal, saidsecond chrominance signal, or a chrominance signal not given said colorcorrection, which is selected by said first selection instrument andsaid second selection instrument, in a pixel of said predeterminedregion.

In addition, the forty-ninth aspect of the present invention is adisplay apparatus which makes one pixel displayable in four colors, thatis, three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising:

color detection instrument which detects whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region;

judgment instrument which judges whether a plurality of chrominancesignals displayed in a pixel of said predetermined region fulfill apredetermined condition;

color correction instrument which performs a first color correction ofincreasing the saturation of said predetermined chrominance component ofsaid chrominance signals and creating a first chrominance signal, and asecond color correction of increasing a white color component of saidchrominance signals and creating a second chrominance signal;

first switching signal generating instrument which generates a firstswitching signal so that said first chrominance signal and said secondchrominance signal may be displayed in turn in every pixel unit, in astate that assumes that all the chrominance signals displayed on a pixelof said predetermined region include said predetermined color component;

second switching signal generating instrument which generates a secondswitching signal so that said first chrominance signal and said secondchrominance signal may be displayed in turn in every plural pixel units,in a state that assumes that all the chrominance signals displayed on apixel of said predetermined region include said predetermined colorcomponent;

switching signal selection instrument which selects said first switchingsignal when said predetermined condition is not fulfilled, and selectssaid second switching signal when said predetermined condition isfulfilled;

first selection instrument which selects said first chrominance signalor said second chrominance signal on the basis of said first switchingsignal or said second switching signal which is selected by saidswitching signal selection instrument;

second selection instrument which selects said first chrominance signalor said second chrominance signal, which is selected by said firstselection instrument, when said predetermined color component isincluded, and selects a chrominance signal, which is not given saidcolor correction, when said predetermined color component is notincluded; and

display instrument which displays said first chrominance signal, saidsecond chrominance signal, or a chrominance signal not given said colorcorrection, which is selected by said first selection instrument andsaid second selection instrument, in a pixel of the predeterminedregion.

The present invention can provide the display apparatus, display method,program, and recording medium capable of decreasing the sense ofincongruity of the visual aspect of color.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing the structure of a display apparatusin a first embodiment of the present invention;

FIG. 2(a) is an explanatory diagram of operation of first signal levelconversion processing instrument in first, third, and fifth embodimentsof the present invention, and FIG. 2(b) is an explanatory diagram ofoperation of second signal level conversion processing instrument infirst, third, and fifth embodiments of the present invention;

FIG. 3 is a drawing showing a display example of a region of a displayscreen, where a yellow color component is included, in the firstembodiment of the present invention;

FIG. 4(a) is a drawing showing the structure of switching signalgeneration instrument in the first embodiment of the present invention,and FIG. 4(b) is a drawing showing the structure of switching signalgeneration instrument, which is different from that in FIG. 4(a), in thefirst embodiment of the present invention;

FIG. 5 is a drawing showing an example of RGB signals in the first,third, and fifth embodiments of the present invention;

FIG. 6 is a block diagram showing the structure of a display apparatusin a second embodiment of the present invention;

FIG. 7 is a block diagram showing the structure of a display apparatusin a third embodiment of the present invention;

FIG. 8 is a drawing showing a display example of a region of a displayscreen, where a yellow color component is included, in the thirdembodiment of the present invention;

FIG. 9 is a drawing showing the structure of switching signal generationinstrument in the third embodiment of the present invention;

FIG. 10 includes drawings showing output result examples of a switchingsignal 126 in the third embodiment of the present invention;

FIG. 11 includes drawings showing output result examples using aswitching signal different from the case of FIG. 10;

FIG. 12 includes drawings showing output result examples of theswitching signal 126 in the case that a black pixel is included in apart of a display region of FIG. 10;

FIG. 13 is a block diagram showing the structure of a display apparatusin a fourth embodiment of the present invention;

FIG. 14 is a block diagram showing the structure of a display apparatusin a fifth embodiment of the present invention;

FIG. 15 is a drawing showing a display example of a region of a displayscreen, where a yellow color component is included, in the fifthembodiment of the present invention;

FIG. 16(a) is a drawing showing the structure of first switching signalgeneration instrument in the fifth embodiment of the present invention,and FIG. 16(b) is a drawing showing the structure of first switchingsignal generation instrument, which is different from that of FIG.16(a), in the fifth embodiment of the present invention;

FIG. 17 includes drawings showing output result examples of a switchingsignal 226 in the fifth embodiment of the present invention;

FIG. 18 includes drawings showing output result examples of theswitching signal 226 in the case that a black pixel is included in apart of a display region of FIG. 17;

FIG. 19 includes drawings showing output result examples of a switchingsignal 231 in the fifth embodiment of the present invention;

FIG. 20 includes drawings showing display examples of a display area,where a checkered pattern is constituted of pastel yellow pixels andblack pixels, in the fifth embodiment of the present invention;

FIG. 21 includes drawings showing examples, where apart of the pastelyellow pixels constituting a checkered pattern of FIG. 19 is changedinto black pixels, in the fifth embodiment of the present invention;

FIG. 22 is an explanatory diagram of pattern detection in the fifthembodiment of the present invention;

FIG. 23 is a structural diagram of pattern detection instrument 213 inthe fifth embodiment of the present invention;

FIG. 24 is a flow chart of a logic operation circuit within the patterndetection instrument 213 in the fifth embodiment of the presentinvention;

FIG. 25 is a block diagram showing the structure of a display apparatusin a sixth embodiment of the present invention;

FIG. 26 includes drawings showing display examples of a display area,where a checkered pattern is constituted of pastel yellow pixels andblack pixels, in the sixth embodiment of the present invention;

FIG. 27 includes drawings showing display examples of a display area,which is constituted of pastel yellow pixels and black pixels, in anmodified example of a seventh embodiment of the present invention;

FIG. 28 is a block diagram showing the structure of a conventionaldisplay apparatus;

FIG. 29 is a drawing showing display screen structure in the case that aconventional display apparatus is a liquid crystal display apparatus;and

FIG. 30 is a drawing showing an example of a display screen of aconventional display apparatus.

Description of Symbols

-   1 Color component separation and detection instrument-   2 First signal level conversion processing instrument-   3 Second signal level conversion processing instrument-   4 Switching signal generation instrument-   5 First selection instrument-   6 Second selection instrument-   7 White color component detection instrument-   8 White display element driving instrument-   9 White display unit-   10 RGB display element driving instrument-   11 RGB display unit-   12 Yellow pixel-   16 White pixel-   20 Frequency divider-   21 Frequency divider-   22 ½ frequency divider-   27 Pseudo-random number generator-   28 Frequency divider-   29 ½ frequency divider-   34 Color component separation and detection instrument-   35 R signal level detection instrument-   36 G signal level detection instrument-   37 B signal level detection instrument-   38 First selection instrument-   39 Second selection instrument-   40 Third selection instrument-   53 Calculation instrument-   101 Color component separation and detection instrument-   102 First signal level conversion processing instrument-   103 Second signal level conversion processing instrument-   104 Switching signal generation instrument-   105 First selection instrument-   106 Second selection instrument-   107 White color component detection instrument-   108 White display element driving instrument-   109 White display unit-   110 RGB display element driving instrument-   111 RGB display unit-   112 Display apparatus-   113 Pastel yellow pixel-   114 White pixel (background)-   115 Yellow pixel-   116 White pixel-   117 Dot clock signal-   118 Horizontal synchronizing signal-   119 Vertical synchronizing signal-   120 Frequency divider-   121 Frequency divider-   122 ½ frequency divider-   201 Color component separation and detection instrument-   202 First signal level conversion processing instrument-   203 Second signal level conversion processing instrument-   204 First switching signal generation instrument-   205 First selection instrument-   206 Second selection instrument-   207 White color component detection instrument-   208 White display element driving instrument-   209 White display unit-   210 RGB display element driving instrument-   211 RGB display unit-   213 Pattern detection instrument-   214 Arithmetic unit

BEST MODE FOR CARRYING OUT THE INVENTION

Hereafter, embodiments of the present invention will be described withreference to drawings.

Embodiment 1

In a first embodiment, a display apparatus will be explained which, evenif a bright yellow (yellow with low saturation), that is, pastel yellowimage portion being surrounded by white or being adjacent to white, candecrease the sense of incongruity that visible color appears differentlysuch as the pastel yellow image portion seeming greenish and the like.

A display apparatus 12 of the first embodiment is shown in FIG. 1.

The display apparatus 12 is constituted of color component separationand detection instrument 1, first signal level conversion processinginstrument 2, second signal level conversion processing instrument 3,switching signal generation instrument 4, first selection instrument 5,second selection instrument 6, white color component detectioninstrument 7, white display element driving instrument 8, white displayunit 9, RGB display element driving instrument 10, and RGB display units11.

The color component separation and detection instrument 1 is theinstrument which performs the separation and detection of a yellow colorcomponent, when the yellow color component is included in RGB signalsinputted.

The first signal level conversion processing instrument 2 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of lowering a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The second signal level conversion processing instrument 3 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of increasing a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The switching signal generation instrument 4 is the instrument whichoutputs a signal for first selection instrument 5 selecting either the Bsignal outputted from the first signal level conversion processinginstrument 2 or the B signal outputted from the second signal levelconversion processing instrument 3.

The first selection instrument 5 is the instrument which selects andoutputs either the B signal outputted from the first signal levelconversion processing instrument 2 or the B signal outputted from thesecond signal level conversion processing instrument 3 on the basis ofthe signal outputted from the switching signal generation instrument 4.

The second selection instrument 6 is the instrument which selects andoutputs either of the B signal outputted from the first selectioninstrument 5, and the B signal among the RGB signals inputted into thedisplay apparatus 12 on the basis of the detection result of the yellowcolor component of the color component separation and detectioninstrument 1.

In addition, since the white color component detection instrument 7,white display element driving instrument 8, white display unit 9, RGBdisplay element driving instrument 10, and RGB display unit 11 are thesame as those of what are explained in the background art, explanationis omitted.

Furthermore, the first signal level conversion processing instrument 2and second signal level conversion processing instrument 3 of thisembodiment are an example of the color correction instrument of thepresent invention, the switching signal generation instrument 4 andfirst selection instrument 5 of this embodiment are an example of theselection instrument of the present invention, the switching signalgeneration instrument 4 and first selection instrument 5 of thisembodiment are an example of height generation instrument of the presentinvention, the white color component detection instrument 7, whitedisplay element driving instrument 8, white display unit 9, RGB displayelement driving instrument 10, and RGB display unit 11 of thisembodiment are an example of the display instrument of the presentinvention, R (red), G (green), and B (blue) colors of this embodimentare an example of three primary colors of the present invention, the RGBsignals of this embodiment are an example of the chrominance signals ofthe present invention, and the yellow color of this embodiment is anexample of the predetermined color of the present invention.

Next, the operation of this embodiment like this will be explained.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 12, such as a personal computer, DVD equipment, ora TV receiver are inputted into the color component separation anddetection instrument 1. In addition, the B signal among the RGB signalsinputted is inputted into the first signal level conversion processinginstrument 2, second signal level conversion processing instrument 3,and first selection instrument 5. In addition, the R signal and G signalamong the RGB signals inputted are inputted into the white colorcomponent detection instrument 7 and RGB display element drivinginstrument 10.

The color component separation and detection instrument 1 detectswhether the RGB signals which are inputted include the yellow colorcomponent.

An example of the RGB signals is shown in FIG. 5. The R signal whichexpresses red, the G signal which expresses green, and the B signalwhich expresses blue are signals which can take 256 kinds of values from0 to 255, respectively, and the larger this value is, the brighter coloris expressed. The green color component 31, yellow color component 32,and white color component 33 are included in the RGB signals of FIG. 5.

It is possible to perform the detection of the yellow color componentfrom the RGB signals, by detecting the case that both of a value of theR signal and a value of the G signal are larger than a value of the Bsignal. Thus, the yellow color component is included in the RGB signalswhen both of the value of the R signal and the value of the G signal arelarger than the value of the B signal.

The color component separation and detection instrument 1 outputs 1 whenthe yellow color component is included in the RGB signals, and itoutputs 0 when the yellow color component is not included in the RGBsignals. Then, the output of the color component separation anddetection instrument 1 is inputted into the second selection instrument6.

On the other hand, the first signal level conversion processinginstrument 2 inputs the B signal among the RGB signals inputted into thedisplay apparatus 12, and performs the conversion of lowering a signallevel of a blue color which is a complementary color of the yellow colorcomponent. In other words, the first signal level conversion processinginstrument 2 performs the conversion of increasing saturation when theyellow color component is included in the RGB signals inputted into thedisplay apparatus 12.

FIG. 2(a) shows the conversion processing which the first signal levelconversion processing instrument 2 performs to the B signal. Thus, thehorizontal axis of FIG. 2(a) shows the value of the B signal among theRGB signals inputted into the first signal level conversion processinginstrument 2, and the vertical axis shows the value of the B signalafter the first signal level conversion processing instrument 2 performsthe conversion processing. The first signal level conversion processinginstrument 2 has stored beforehand a conversion table for performing theconversion processing shown in FIG. 2(a), and performs the conversionprocessing of FIG. 2(a) using the conversion table. In addition,although it is explained that the first signal level conversionprocessing instrument 2 performs the conversion processing shown in FIG.2(a) using the conversion table, it is not limited to this. For example,the conversion processing of FIG. 2(a) may be performed using a methodother than the conversion table, such as performing the conversionprocessing shown in FIG. 2(a) by operation processing by hardware orsoftware.

Apparently from FIG. 2(a), when the value of the B signal inputted intothe first signal level conversion processing instrument 2 is smallerthan a predetermined value, the value of the B signal outputted from thefirst signal level conversion processing instrument 2 is set at 0. Then,when the value of the B signal inputted into the first signal levelconversion processing instrument 2 is larger than the predeterminedvalue, the value of the B signal outputted from the first signal levelconversion processing instrument 2 is set at a value larger than 0, butit is set at a value smaller than the value of B signal inputted intothe first signal level conversion processing instrument 2. In this way,since the first signal level conversion processing instrument 2 convertsthe value of the B signal inputted as shown in FIG. 2(a), the value ofthe B signal in the RGB signals outputted from the first signal levelconversion processing instrument 2 becomes small in comparison with theRGB signals at the time of an input. Thus, when the RGB signals inputtedinto the display apparatus 12 includes the yellow color component 32 asshown in FIG. 5, RGB signals are newly constituted from the B signaloutputted from the first signal level conversion processing instrument2, and the R signal and G signal which are inputted into the displayapparatus 12, and then, the constituted RGB signals become signals wheresaturation increases in comparison with the RGB signals inputted intothe display apparatus 12.

In addition, the second signal level conversion processing instrument 3performs the conversion of increasing a signal level of a blue color,which is a complementary color of the yellow color component, to the Bsignal among the RGB signals inputted into the display apparatus 12. Inother words, the second signal level conversion processing instrument 3performs the conversion of increasing a white color component when theyellow color component is included in the RGB signals inputted into thedisplay apparatus 12.

FIG. 2(b) shows the conversion processing which the second signal levelconversion processing instrument 3 performs to the B signal. Thus, thehorizontal axis of FIG. 2(b) shows the value of the B signal among theRGB signals inputted into the second signal level conversion processinginstrument 3, and the vertical axis shows the value of the B signalafter the third signal level conversion processing instrument 3 performsthe conversion processing. The second signal level conversion processinginstrument 3 has stored beforehand a conversion table for performing theconversion processing shown in FIG. 2(b), and performs the conversionprocessing of FIG. 2(b) using the conversion table. In addition,although it is explained that the second signal level conversionprocessing instrument 3 performs the conversion processing shown in FIG.2(b) using the conversion table, it is not limited to this. For example,the conversion processing of FIG. 2(b) may be performed using a methodother than the conversion table, such as performing the conversionprocessing shown in FIG. 2(b) by operation processing by hardware orsoftware.

Apparently from FIG. 2(b), the value of the B signal among the RGBsignals outputted from the second signal level conversion processinginstrument 3 becomes a value larger than the value of the B signal amongthe RGB signals inputted into the second signal level conversionprocessing instrument 3. In this way, since the second signal levelconversion processing instrument 3 converts the value of the B signalamong the RGB signals inputted as shown in FIG. 2(b), the value of the Bsignal outputted from the second signal level conversion processinginstrument 3 becomes large in comparison with the RGB signals at thetime of an input. Thus, when the RGB signals inputted into the displayapparatus 12 include the yellow color component 32, when RGB signals arenewly constituted by synthesizing the B signal, outputted from thesecond signal level conversion processing instrument 3, with the Rsignal and G signal inputted into the display apparatus 12, theconstituted RGB signals become signals where the white color componentincreases in comparison with the RGB signals inputted into the displayapparatus 12.

The switching signal generation instrument 4 generates a switchingsignal using a dot clock, a horizontal synchronizing signal, and avertical synchronizing signal for determining the timing with which theRGB display element driving instrument 10 and the white display elementdriving instrument 8 of the display apparatus 12 drives the RGB displayunit 11 and white display unit 9, and outputs it to the first selectioninstrument 5. This switching signal is a signal of taking a value ofeither 1 or 0. In addition, the operation of the switching signalgeneration instrument 4 will be described later.

The first selection instrument 5 selects the B signal outputted from thefirst signal level conversion processing instrument 2 when the value ofthe switching signal outputted from the switching signal generationinstrument 4 is 1, and outputs it to the second selection instrument 6,and selects the B signal outputted from the second signal levelconversion processing instrument 3 when the value of the switchingsignal is 0, and outputs it to the second selection instrument 6.

When the value of the signal which the color component separation anddetection instrument 1 outputs is 1, that is, when the yellow colorcomponent is included, the second selection instrument 6 selects the Bsignal outputted from the first selection instrument 5, and outputs itto the RGB display element driving instrument 10 and white colorcomponent detection instrument 7. In addition, when the value of thesignal which the color component separation and detection instrument 1outputs is 0, that is, when the yellow color component is not included,the second selection instrument 6 outputs the B signal among the RGBsignals, inputted into the display apparatus 12, without conversionprocessing to the RGB display element driving instrument 10 and whitecolor component detection instrument 7.

Thus, the R signal and G signal which are inputted into the displayapparatus 12, and the B signal outputted from the second selectioninstrument 6 are inputted into the RGB display element drivinginstrument 10 and white color component detection instrument 7. Then,the white color component detection instrument 7 and RGB display elementdriving instrument 10 process these R signals, G signal, and B signal asnew RGB signals.

In addition, the operation of the white color component detectioninstrument 7, white display element driving instrument 8, white displayunit 9, RGB display element driving instrument 10, and RGB display unit11 is the same as that of what are explained in the background art.

In this way, an image is displayed on a display screen.

By the way, the switching signal which the switching signal generationinstrument 4 outputs, for example, such a signal that the value of theswitching signal becomes 0 in a pixel adjacent to a certain pixel in ahorizontal direction when the value of the switching signal is 1 to thecertain pixel, and, the value of the switching signal becomes 1 in afurther adjacent pixel horizontally. Thus, when attention is paid to ahorizontal pixel row, the switching signal takes 0 and 1 in turn.Similarly, when attention is paid to a vertical pixel column, theswitching signal takes 0 and 1 in turn.

Hence, yellow pixels 15 and white pixels 16 in FIG. 3 will bealternately displayed in a region of the display screen where the yellowcolor component is included in the inputted RGB signals, that is, aregion of the display screen which a plurality of pixels having a yellowcolor component in the inputted RGB signals exist adjacently. Thus, whena plurality of pixels which have a yellow color component in theinputted RGB signals do not exist adjacently, that is, when only onepixel having a yellow color component exists by itself, such analternating display cannot be performed. Hence, such an alternatingdisplay is performed to a region of the display screen where a pluralityof pixels having a yellow color component in the inputted RGB signalsexists adjacently. Here, the yellow pixels 15 are those into which theRGB signals outputted from the first signal level conversion processinginstrument 2 are displayed, and are the RGB signals which are givenconversion processing so that saturation may increase. In addition, thewhite pixels 16 are those into which the RGB signals outputted from thesecond signal level conversion processing instrument 3 are displayed,and are the RGB signals which are given conversion processing so thatsaturation may be lowered.

In addition, the region of the display screen where the yellow colorcomponent is included in the inputted RGB signals in this embodiment isan example of the region where a plurality of pixels having a componentwith the above-mentioned predetermined color in the present inventionexists adjacently.

Here, in the region of the display screen where the yellow colorcomponent is included in the inputted RGB signals, let the RGB signalswhich is constituted of the B signal where a value of the output of thefirst signal level conversion processing instrument 2 is decreased, andthe R signal and G signal which are inputted into the display apparatus12 be first RGB signals, and let the RGB signals which is constituted ofthe B signal where a value of the output of the second signal levelconversion processing instrument 3 is increased, and the R signal and Gsignal which are inputted into the display apparatus 12 be second RGBsignals. Then, the first RGB signals are signals where saturation isincreased, and the second RGB signals are RGB signals whose white colorcomponent is increased. In such a region, the first RGB signals andsecond RGB signals will be displayed in a checkered pattern, as shown inthe yellow pixels 15 and white pixels 16, respectively in FIG. 3. Inthis way, the display apparatus 12 gives the height difference insaturation to the region of the display screen by performing display atevery pixel of the region in the region of the display screen, where theyellow color component is included in the inputted RGB signals, usingeither of the RGB signals where saturation is increased, and the RGBsignals where the white color component is increased.

Hence, for example, bright yellow (yellow with low saturation), that is,pastel yellow will be displayed with the yellow pixels 15 whosesaturation is increased more, and the white pixels 16 where the whitecolor component is increased more. Hence, it will be felt to human eyesby the integration effect of human eyes that bright yellow (yellow withlow saturation), that is, pastel yellow is displayed. Further, since itis possible to increase the brightness of an image portion by displayingbright yellow (yellow with low saturation), that is, pastel yellow bythe alternating display with the yellow whose saturation is increasedmore, and the yellow where the white color component is increased more,even if the image portion being surrounded by white or being adjacent towhite, it is possible to decrease the sense of incongruity that visiblecolor appears differently, e.g., the image portion seems greenish.

In addition, although bright yellow (yellow with low saturation), thatis, pastel yellow is expressed by the alternating display of the yellowpixels 15 and the white pixels 16 every pixel for a region of thedisplay screen where the yellow color component is included in theinputted RGB signals in FIG. 3, an equivalent effect can be obtainedalso by temporally alternating display. Thus, when a certain pixel isdisplayed with the B signal outputted from the first signal levelconversion processing instrument 2, and the R signal and G signal whichare inputted into the display apparatus 12, it is possible to display itwith the B signal outputted from the second signal level conversionprocessing instrument 3, and the R signal and G signal which areinputted into the display apparatus 12 when the next field or the nextframe is displayed. Thus, an equivalent effect can be obtained also byswitching and displaying the B signal outputted from the first signalprocessing instrument 2, and the B signal outputted from the secondsignal processing instrument 3, at every field or every frame. In thisway, an effect equivalent to this embodiment can be obtained also byswitching and displaying either of the RGB signals where saturation isincreased, and the RGB signals where the white color component isincreased, at every field or every frame temporally.

Nevertheless, “when the next field is displayed” is a case of interlace,and shall mean the case of displaying a second field from the presentfield, when one frame is displayed by an odd number field and an evennumber field. In addition, “switching and displaying the B signaloutputted from the first signal processing instrument 2, and the Bsignal outputted from the second signal processing instrument 3, atevery field” is a case of an interlace mode, and means “switching anddisplaying the B signal outputted from the first signal processinginstrument 2, and the B signal outputted from the second signalprocessing instrument 3, at every 2 fields, when one frame is displayedwith an odd number field and an even number field”. Hereafter similarly,in the first embodiment and second embodiment, “switching display atevery field” is a case of the interlace mode, and means “switchingdisplay at every 2 fields when one frame is displayed with an odd numberfield and an even number field”.

Now, as mentioned above, the switching signal generation instrument 4will be explained.

FIG. 4(a) shows the structure of the switching signal generationinstrument 4. The switching signal generation instrument 4 isconstituted of a frequency divider 20, a frequency divider 21, a½-frequency divider 22, and calculation instrument 53.

The frequency divider 20 is the instrument which inputs a dot clocksignal 17 for the white display element driving instrument 8 and RGBdisplay element driving instrument 10 to determine the timing of displayat every pixel, performing frequency dividing, and outputting a pixelalternating signal 23. The frequency divider 21 is the instrument whichinputs a horizontal synchronizing signal 18 for the white displayelement driving instrument 8 and RGB display element driving instrument10 to determine the timing of display every horizontal period, performsfrequency dividing, and outputs a line alternating signal 24. The ½frequency divider 22 is the instrument which inputs a verticalsynchronizing signal 19 for the white display element driving instrument8 and RGB display element driving instrument 10 to determine the timingof display in every frame or field, performs frequency dividing, andoutputs a field alternating signal 25. The calculation instrument 53 isthe instrument which obtains the exclusive OR of the pixel alternatingsignal 23, line alternating signal 24, and field alternating signal 25,and outputs the obtained exclusive OR as a switching signal 26.

Thus, the dot clock signal 17 is inputted into the frequency divider 20,the frequency divider 20 performs the frequency dividing of the dotclock signal 17, and outputs the pixel alternating signal 23.

In addition, the horizontal synchronizing signal 18 is inputted into thefrequency divider 20 and frequency divider 21. The frequency divider 20is reset in the initial state in the timing when the horizontalsynchronizing signal 18 is inputted. In addition, the frequency divider21 performs the frequency dividing of the horizontal synchronizingsignal 18, and outputs the line alternating signal 24.

Furthermore, the vertical synchronizing signal 19 is inputted into thefrequency divider 21 and ½ frequency divider 22. The frequency divider21 is reset in the initial state when the vertical synchronizing signal19 is inputted. In addition, the ½ frequency divider 22 performs the ½frequency dividing of the vertical synchronizing signal 19, and outputsthe field alternating signal 25.

The calculation instrument 53 inputs the pixel alternating signal 23,line alternating signal 24, and field alternating signal 25, obtains theexclusive OR of them, and outputs it as the switching signal 26.

When the frequency divider 20 and the frequency divider 21 perform the ½frequency dividing of the dot clock signal 17 and horizontalsynchronizing signal 18, respectively, the switching signal 26 becomeswhat expresses a checkered pattern.

By using the switching signal generation instrument 4 of FIG. 4(a), aregion, where a yellow color component is included, in the displayscreen will be displayed with the B signal outputted from the firstsignal level conversion instrument 2, and the B signal outputted fromthe second signal level conversion processing instrument 3. Thus, byusing the switching signal generation instrument 4 of FIG. 4(a), theregion, where the yellow color component is included, in the displayscreen will be displayed with the B signal outputted from the firstsignal level conversion instrument 2 and the B signal outputted from thesecond signal level conversion processing instrument 3 being switchedevery pixel. In addition, when attention is paid to a specific pixel,when the yellow color component is included in the display screen, the Bsignal outputted from the first signal level conversion processinginstrument 2 and the B signal outputted from the second signal levelconversion processing instrument 3 will be switched and displayed everyfield.

In addition, FIG. 4(b) shows another structure of the switching signalgeneration instrument 4. The switching signal generation instrument 4 ofFIG. 4(b) is constituted of a pseudo-random number generator 27, afrequency divider 28, a ½ frequency divider 29, and calculationinstrument 53.

The pseudo-random number generator 27 is the instrument which inputs thedot clock signal 17 for the white display element driving instrument 8and RGB display element driving instrument 10 to determine the timing ofdisplay every pixel, generates a pseudo-random number using the inputteddot clock signal 27, and outputs it as the pixel alternating signal 23.The frequency divider 28 is the instrument which inputs the horizontalsynchronizing signal 18 for the white display element driving instrument8 and RGB display element driving instrument 10 to determine the timingof the display every horizontal period, performs frequency dividing, andoutputs the line alternating signal 24. The ½ frequency divider 22 isthe instrument which inputs the vertical synchronizing signal 19 for thewhite display element driving instrument 8 and RGB display elementdriving instrument 10 to determine the timing of display in every frameor field, performs frequency dividing, and outputs a field alternatingsignal 25. The calculation instrument 53 is the instrument which obtainsthe exclusive OR of the pixel alternating signal 23, line alternatingsignal 24, and field alternating signal 25, and outputs the obtainedexclusive OR as a switching signal 26.

Thus, the dot clock signal 17 is inputted into the pseudo-random numbergenerator 27, and the pseudo-random number generator 27 generates apseudo-random number using the inputted dot clock signal 17, and outputsthe generated pseudo-random number as a pixel alternating signal 23.

In addition, the horizontal synchronizing signal 18 is inputted into thepseudo-random number generator 27 and frequency divider 28. Thepseudo-random number generator 27 is reset in the initial state at thetiming when the horizontal synchronizing signal 18 is inputted. Inaddition, the frequency divider 28 performs the frequency dividing ofthe horizontal synchronizing signal 18, and outputs the line alternatingsignal 24.

Furthermore, the vertical synchronizing signal 19 is inputted into thefrequency divider 28 and the ½ frequency divider 229. The frequencydivider 28 is reset in the initial state when the vertical synchronizingsignal 19 is inputted. In addition, the ½ frequency divider 29 performsthe ½ frequency dividing of the vertical synchronizing signal 19, andoutputs the field alternating signal 25.

The calculation instrument 53 inputs the pixel alternating signal 23,line alternating signal 24, and field alternating signal 25, obtains theexclusive OR of them, and outputs it as the switching signal 26.

By using the switching signal generation instrument 4 of FIG. 4(b), aregion, where a yellow color component is included, in the displayscreen will be displayed in a random pattern with the B signal outputtedfrom the first signal level conversion instrument 2, and the B signaloutputted from the second signal level conversion processing instrument3. In addition, when attention is paid to a specific pixel, when theyellow color component is included in the pixel, the B signal outputtedfrom the first signal level conversion processing instrument 2 and the Bsignal outputted from the second signal level conversion processinginstrument 3 is switched and displayed every field. The use of theswitching signal generation instrument 4 of FIG. 4(b) can obtain aneffect equivalent to that obtained by using the switching signalgeneration instrument 4 of FIG. 4(a).

In addition, although it is explained in this embodiment that RGBsignals are inputted into the display apparatus 12, it is not limited tothis, but signals which express colors except RGB signals may beinputted.

Furthermore, although the display apparatus 41 performs the processing,which decreases the sense of incongruity of yellow appearance, in thisembodiment, it is also possible to perform the processing whichdecreases the sense of incongruity of magenta or cyan.

Moreover, although the conversion which the first signal levelconversion processing instrument 2 gives to a blue signal is linearconversion at a predetermined intensity level or higher as shown in FIG.2(a) in this embodiment, nonlinear conversion is acceptable. In short,the first signal level conversion processing instrument 2 has only toconvert the B signal inputted into the first signal level conversionprocessing instrument 2 so as to be a small value in comparison with theB signal at the time of an input.

Furthermore, in this embodiment, although the conversion which thesecond signal level conversion processing instrument 3 gives to the bluesignal is linear conversion up to the predetermined intensity level, itmay be nonlinear conversion. In short, the second signal levelconversion processing instrument 3 has only to convert the B signalinputted into the first signal level conversion processing instrument 2so as to be a large value in comparison with the B signal at the time ofthe input.

Moreover, in this embodiment, although it is explained that thepseudo-random number generator 27 is reset in the initial state at thetiming when the horizontal synchronizing signal 18 is inputted, it isnot limited to this. The pseudo-random number generator 27 may be notreset in the initial state at the timing when the horizontalsynchronizing signal 18 is inputted.

Embodiment 2

Next, a second embodiment will be explained.

In the first embodiment, the display apparatus is explained which, evenif a bright yellow (yellow with low saturation), that is, pastel yellowimage portion being surrounded by white or being adjacent to white, candecrease the sense of incongruity that visible color appears differentlysuch as the pastel yellow image portion seeming greenish and the like.In the second embodiment, the display apparatus will be explained which,even if an image portion which is bright yellow (yellow with lowsaturation), that is, pastel yellow, bright magenta (magenta with lowsaturation), that is, pastel magenta, and bright cyan (cyan with lowsaturation), that is, pastel cyan being surrounded by white or beingadjacent to white, can decrease the sense of incongruity that visiblecolor appears differently.

The structure of a display apparatus 41 of the second embodiment isshown in FIG. 6.

The display apparatus 41 is constituted of color component separationand detection instrument 34, the switching signal generation instrument4, R signal level conversion processing instrument 35, G signal levelconversion processing instrument 36, B signal level conversionprocessing instrument 37, first selection instrument 38, secondselection instrument 39, third selection instrument 40, the white colorcomponent detection instrument 7, the white display element drivinginstrument 8, the white display unit 9, the RGB display element drivinginstrument 10, and the RGB display units 11.

The color component separation and detection instrument 34 is theinstrument which outputs a yellow color component detection signalshowing whether a yellow color component is included in the RGB signalsinputted, outputs a magenta color component detection signal showingwhether a magenta component is included in the RGB signals inputted, andoutputs a cyan color component detection signal showing whether a cyancomponent is included in the RGB signals inputted.

The switching signal generation instrument 4 is equivalent to what isexplained in the first embodiment.

The R signal level conversion instrument 35 is the instrument whichperforms the first color correction of lowering a signal level of a redcolor, which is a complementary color of a cyan color component, to an Rsignal among the RGB signals inputted, and the second color correctionof increasing a red signal level, and outputs the R signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 4.

The G signal level conversion instrument 36 is the instrument whichperforms the first color correction of lowering a signal level of agreen color, which is a complementary color of a magenta colorcomponent, to an G signal among the RGB signals inputted, and the secondcolor correction of increasing a green signal level, and outputs the Gsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 4.

The B signal level conversion instrument 37 is the instrument whichperforms the first color correction of lowering a signal level of a bluecolor, which is a complementary color of a yellow color component, to aB signal among the RGB signals inputted, and the second color correctionof increasing a blue signal level, and outputs the B signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 4.

The B signal level conversion instrument 37 is equivalent to the firstsignal level conversion processing instrument 2, second signal levelconversion processing instrument 3, and first selection instrument 5 ofthe display apparatus 12 of the first embodiment.

In addition, the R signal level conversion instrument 35 is equivalentto the case that, in the first signal level conversion processinginstrument 2, second signal level conversion processing instrument 3,and first selection instrument 5 of the display apparatus 12 of thefirst embodiment, color correction equivalent to the color correctionwhich the first signal level conversion processing instrument 2 andsecond signal level conversion processing instrument 3 have given to ablue color is given to a red color using a conversion table optimized toa red color.

Furthermore, the G signal level conversion instrument 36 is equivalentto the case that, in the first signal level conversion processinginstrument 2, second signal level conversion processing instrument 3,and first selection instrument 5 of the display apparatus 12 of thefirst embodiment, color correction equivalent to the color correctionwhich the first signal level conversion processing instrument 2 andsecond signal level conversion processing instrument 3 have given to ablue color is given to a green color using a conversion table optimizedto a green color.

The first selection instrument 38 is the instrument which selects andoutputs either of the R signal outputted from the R signal levelconversion instrument 35, and the R signal among the RGB signalsinputted into the display apparatus 41 on the basis of a cyan componentdetection signal, that is, the detection result of the cyan component ofthe color component separation and detection instrument 34.

The second selection instrument 39 is the instrument which selects andoutputs either of the G signal outputted from the G signal levelconversion instrument 36, and the G signal among the RGB signalsinputted into the display apparatus 41 on the basis of a magentacomponent detection signal, that is, the detection result of the magentacomponent of the color component separation and detection instrument 34.

The third selection instrument 40 is the instrument which selects andoutputs either of the B signal outputted from the B signal levelconversion instrument 35, and the B signal among the RGB signalsinputted into the display apparatus 41 on the basis of a yellow colorcomponent detection signal, that is, the detection result of the yellowcolor component of the color component separation and detectioninstrument 34.

In addition, since the white color component detection instrument 7,white display element driving instrument 8, white display unit 9, RGBelement driving instrument 10, and RGB display unit 11 are the same asthose of what are explained in the background art, explanation isomitted.

Furthermore, the R signal level conversion instrument 35, G signal levelconversion instrument 36, and B signal level conversion instrument 37 ofthis embodiment are an example of the color correction instrument of thepresent invention, the switching signal generation instrument 4, firstselection instrument 38, second selection instrument 39, and thirdselection instrument 40 of this embodiment are an example of theselection instrument of the present invention, the switching signalgeneration instrument 4, first selection instrument 38, second selectioninstrument 39, and third selection instrument 40 of this embodiment arean example of the height generation instrument of the present invention,the white color component detection instrument 7, white display elementdriving instrument 8, white display unit 9, RGB display element drivinginstrument 10, and RGB display unit 11 of this embodiment are an exampleof the display instrument of the present invention, R (red), G (green),and B (blue) colors of this embodiment are an example of three primarycolors of the present invention, the RGB signals of this embodiment arean example of the chrominance signals of the present invention, and theyellow color, magenta color, and cyan color of this embodiment areexamples of the predetermined color of the present invention.

Next, the operation of this embodiment like this will be explained.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 41, such as a personal computer, DVD equipment, ora TV receiver are inputted into the color component separation anddetection instrument 34. In addition, the R signal among the RGB signalsinputted is inputted into the R signal level conversion instrument 35and first selection instrument 38, the G signal among the RGB signalsinputted is inputted into the G signal level conversion instrument 36and second selection instrument 39, and the B signal among the RGBsignals inputted is inputted into the B signal level conversioninstrument 37 and third selection instrument 40.

The color component separation and detection instrument 34 outputs 1 tothe first selection instrument 38 as a cyan color component detectionsignal, when the cyan color component is included in the RGB signalsinputted, and outputs 0 to the first selection instrument 38 as the cyancolor component detection signal when the cyan component is not includedin the RGB signals inputted.

In addition, the color component separation and detection instrument 34outputs 1 to the second selection instrument 39 as a magenta colorcomponent detection signal, when the magenta color component is includedin the RGB signals inputted, and outputs 0 to the second selectioninstrument 39 as the magenta color component detection signal when themagenta component is not included in the RGB signals inputted.

Furthermore, the color component separation and detection instrument 34outputs 1 to the third selection instrument 40 as a yellow colorcomponent detection signal, when the yellow color component is includedin the RGB signals inputted, and outputs 0 to the third selectioninstrument 40 as the yellow color component detection signal when theyellow color component is not included in the RGB signals inputted.

On the other hand, the R signal level conversion instrument 35 performsthe first color correction of lowering a signal level of a red color,which is a complementary color of a cyan color component, to an R signalinputted, and the second color correction of increasing a red signallevel. Then, it outputs to the first selection instrument 38 the Rsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 4.

Then, the first selection instrument 38 selects the R signal outputtedfrom the R signal level conversion instrument 35 when the cyan colorcomponent detection signal outputted from the color component separationand detection instrument 34 is 1, that is, a cyan color component isincluded in the RGB signals which is inputted into the display apparatus41, and outputs it to the white color component detection instrument 7and RGB display element driving instrument 10. On the other hand, thefirst selection instrument 38 selects the R signal among the RGBsignals, which is inputted into the display apparatus 41, when the cyancolor component detection signal outputted from the color componentseparation and detection instrument 34 is 0, that is, a cyan colorcomponent is not included in the RGB signals which is inputted into thedisplay apparatus 41, and outputs it to the white color componentdetection instrument 7 and RGB display element driving instrument 10.

The G signal level conversion instrument 36 performs the first colorcorrection of lowering a signal level of a green color, which is acomplementary color of a magenta color component, to a G signalinputted, and the second color correction of increasing a green signallevel. Then, it outputs to the second selection instrument 39 the Gsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 4.

Then, the second selection instrument 39 selects the G signal outputtedfrom the G signal level conversion instrument 36 when the magenta colorcomponent detection signal outputted from the color component separationand detection instrument 34 is 1, that is, a magenta color component isincluded in the RGB signals which is inputted into the display apparatus41, and outputs it to the white color component detection instrument 7and RGB display element driving instrument 10. On the other hand, thesecond selection instrument 39 selects the G signal among the RGBsignals, which is inputted into the display apparatus 41, when themagenta color component detection signal outputted from the colorcomponent separation and detection instrument 34 is 0, that is, amagenta color component is not included in the RGB signals which isinputted into the display apparatus 41, and outputs it to the whitecolor component detection instrument 7 and RGB display element drivinginstrument 10.

The B signal level conversion instrument 37 performs the first colorcorrection of lowering a signal level of a blue color, which is acomplementary color of a yellow color component, to a B signal inputted,and the second color correction of increasing a blue signal level. Then,it outputs to the third selection instrument 40 the B signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 4.

Then, the third selection instrument 40 selects the B signal outputtedfrom the B signal level conversion instrument 37 when the yellow colorcomponent detection signal outputted from the color component separationand detection instrument 34 is 1, that is, a yellow color component isincluded in the RGB signals which is inputted into the display apparatus41, and outputs it to the white color component detection instrument 7and RGB display element driving instrument 10. On the other hand, thethird selection instrument 40 selects the B signal among the RGBsignals, which is inputted into the display apparatus 41, when theyellow color component detection signal outputted from the colorcomponent separation and detection instrument 34 is 0, that is, a yellowcolor component is not included in the RGB signals which is inputtedinto the display apparatus 41, and outputs it to the white colorcomponent detection instrument 7 and RGB display element drivinginstrument 10.

The operation of the white color component detection instrument 7, whitedisplay element driving instrument 8, white display unit 9, RGB displayelement driving instrument 10, and RGB display unit 11 is the same asthat of what are explained in the background art.

In this way, an image is displayed on a display screen.

Here, since the RGB signals including both a yellow color component anda magenta color component, RGB signals including both a yellow colorcomponent and a cyan component, and RGB signals including both a magentacomponent and a cyan component do not exist, two or more of the yellowcolor component detection signal, magenta color component detectionsignal, and a cyan color component detection signal never take 1. Thus,there is only either a case that all values of the yellow colorcomponent detection signal, magenta color component detection signal,and cyan color component detection signal become 0, or a case that anyone signal takes 1.

Hence, display is performed as follows by using the switching signalgeneration instrument 4 of FIG. 4(a) as the switching signal generationinstrument 4. Thus, a region, where the yellow color component, magentacolor component, or cyan color component is included, in a displayscreen is displayed, for example as a checkered pattern or the like,which is constituted of the RGB signals where saturation is increased,and the RGB signals where the white color component is increased, andwith attention being paid to one pixel, it is also alternately displayedwith the RGB signals where saturation is increased every field or frame,and the RGB signals where the white color component is increased.

In addition, display is performed as follows by using the switchingsignal generation instrument 4 of FIG. 4(b) as the switching signalgeneration instrument 4. Thus, a region, where the yellow colorcomponent, magenta color component, or cyan color component is included,in the display screen is displayed in a random pattern, which is made ofthe RGB signals where saturation is increased, and the RGB signals wherethe white color component is increased, and with attention being paid toone pixel, it is also alternately displayed with the RGB signals wheresaturation is increased every field or frame, and the RGB signals wherethe white color component is increased.

In this way, alternating display is performed like a checkered patternor the like in a region of the display screen where the yellow colorcomponent, magenta color component, or cyan color component is includedin the inputted RGB signals, that is, a region of the display screenwhere a plurality of pixels having the yellow color component, magentacolor component, or cyan color component in the inputted RGB signalsexist adjacently. Thus, when a plurality of pixels which have the yellowcolor component, magenta color component, or cyan color component in theinputted RGB signals do not exist adjacently, that is, when only onepixel having a yellow color component, magenta color component, or cyancolor component exists by itself, such an alternating display cannot beperformed. Hence, such an alternating display is performed to a regionof the display screen where a plurality of pixels having a yellow colorcomponent, magenta color component, or cyan color component in theinputted RGB signals exist adjacently. In this way, height difference insaturation is given to a region of the display screen by performingdisplay at every pixel of the region in the region of the displayscreen, where the yellow color component, magenta color component, orcyan color component is included in the inputted RGB signals, usingeither of the RGB signals where saturation is increased, and the RGBsignals where the white color component is increased.

In addition, the region of the display screen where the yellow colorcomponent, magenta color component, or cyan color component is includedin the inputted RGB signals in this embodiment is an example of theregion where a plurality of pixels having a component with theabove-mentioned predetermined color in the present invention existsadjacently.

In addition, the region on a display screen where the yellow colorcomponent, magenta color component, or cyan color component is includedmay be displayed, for example, as a checkered pattern or the like, andalternating display may not be performed every field. In addition, sucha region may be displayed as a random pattern and alternating displaymay not be performed every field. Furthermore, such a region isdisplayed in one field or one frame by either of the RGB signals, wheresaturation is increased, and the RGB signals where the white colorcomponent is increased, and alternating display may be performed withthe RGB signals where saturation is increased every field or everyframe, and the RGB signals where the white color component is increased.However, in the case of displaying with either of the RGB signals wheresaturation is increased, and the RGB signals, where the white colorcomponent is increased, in one field or one frame, and performing thealternating display with the RGB signals where saturation is increased,and the RGB signals, where the white color component is increased, everyfield or every frame, a flicker arises when the number of fields orframes displayed in 1 second is small, and hence, it is necessary toenlarge sufficiently the number of fields or frames displayed in 1second.

In the first embodiment, even if a bright yellow (yellow with lowsaturation), that is, pastel yellow image portion being surrounded bywhite or being adjacent to white, it was possible to decrease the senseof incongruity that visible color appears differently such as the pastelyellow image portion seeming greenish and the like. In the secondembodiment, it is possible to decrease the sense of incongruity thatvisible color appears differently for not only bright yellow (yellowwith low saturation), that is, pastel yellow, but also bright magenta(magenta with low saturation), that is, pastel magenta, and bright cyan(cyan with low saturation), that is, pastel cyan even if its imageportion is surrounded by white or is adjacent to white.

In addition, although it was explained in this embodiment that the senseof incongruity of appearance of yellow, magenta, and cyan was decreased,it is also possible to decrease the sense of incongruity of appearanceof two or one of these three colors. For example, when decreasing thesense of incongruity of appearance of only magenta, it is not necessaryto provide the R signal level conversion instrument 35, first selectioninstrument 38, B signal level conversion instrument 37, and thirdselection instrument 40.

Embodiment 3

Next, a third embodiment will be explained.

In the third embodiment, similarly to the first embodiment, a displayapparatus will be explained which, even if a bright yellow (yellow withlow saturation), that is, pastel yellow image portion being surroundedby white or being adjacent to white, can decrease the sense ofincongruity that visible color appears differently such as the pastelyellow image portion seeming greenish and the like.

FIG. 7 is a block diagram showing the structure of a display apparatus112 of the third embodiment.

The display apparatus 112 is constituted of color component separationand detection instrument 101, first signal level conversion processinginstrument 102, second signal level conversion processing instrument103, switching signal generation instrument 104, first selectioninstrument 105, second selection instrument 106, white color componentdetection instrument 107, white display element driving instrument 108,a white display unit 109, RGB display element driving instrument 110,and an RGB display unit 111.

The color component separation and detection instrument 101 is theinstrument which performs the separation and detection of a yellow colorcomponent, when the yellow color component is included in RGB signalsinputted.

The first signal level conversion processing instrument 102 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of lowering a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The second signal level conversion processing instrument 103 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of increasing a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The switching signal generation instrument 104 is the instrument whichoutputs a signal for first selection instrument 105 selecting either theB signal outputted from the first signal level conversion processinginstrument 102 or the B signal outputted from the second signal levelconversion processing instrument 103.

The first selection instrument 105 is the instrument which selects andoutputs either the B signal outputted from the first signal levelconversion processing instrument 102 or the B signal outputted from thesecond signal level conversion processing instrument 103 on the basis ofthe signal outputted from the switching signal generation instrument104.

The second selection instrument 106 is the instrument which selects andoutputs either of the B signal outputted from the first selectioninstrument 105, and the B signal among the RGB signals inputted into thedisplay apparatus 112 on the basis of the detection result of the yellowcolor component of the color component separation and detectioninstrument 101.

In addition, since the white color component detection instrument 107,white display element driving instrument 108, white display unit 109,RGB display element driving instrument 110, and RGB display unit 111 arethe same as those of what are explained in the background art,explanation is omitted.

Furthermore, an example of color detection instrument of the presentinvention is equivalent to the color component separation instrument 101in this third embodiment, and an example of color correction instrumentof the present invention is equivalent to the first signal levelconversion processing instrument 102 and second signal level conversionprocessing instrument 103 in this third embodiment. Moreover, thecontrol instrument of the present invention is equivalent to theswitching signal generating instrument 104, first selection instrument105, and second selection instrument 106 in this third embodiment.Moreover, an example of display instrument of the present invention isequivalent to the white color component detection instrument 107, whitedisplay element driving instrument 108, white display unit 109, RGBdisplay element driving instrument 110, and RGB display unit 111.

In addition, an example of the three primary colors of the presentinvention is equivalent to an R (red) color, a G (green) color, and a B(blue) color in this third embodiment. An example of the chrominancesignals of the present invention is equivalent to the RGB signals inthis third embodiment, and an example of the predetermined colorcomponent of the present invention is equivalent to yellow in this thirdembodiment.

Next, an example of a display method of the present invention is alsoconcurrently explained with the operation of the display apparatus,having the above-mentioned structure, in this third embodiment.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 112, such as a personal computer, DVD equipment,or a TV receiver are inputted into the color component separation anddetection instrument 110. In addition, the B signal among the RGBsignals inputted is inputted into the first signal level conversionprocessing instrument 102, second signal level conversion processinginstrument 103, and second selection instrument 106. Furthermore, the Rsignal and G signal among the RGB signals inputted are inputted into thewhite color component detection instrument 107 and RGB display elementdriving instrument 110.

The color component separation and detection instrument 101 detectswhether the RGB signals which is inputted includes the yellow colorcomponent (this is equivalent to an example of the color detection stepof the present invention).

An example of the RGB signals is shown in FIG. 5. The R signal whichexpresses red, the G signal which expresses green, and the B signalwhich expresses blue are signals which can take 256 kinds of values from0 to 255, respectively, and the larger this value is, the brighter coloris expressed. The green color component 31, yellow color component 32,and white color component 33 are included in the RGB signals of FIG. 5.

It is possible to perform the detection of the yellow color componentfrom the RGB signals, by detecting the case that both of a value of theR signal and a value of the G signal are larger than a value of the Bsignal. Thus, the yellow color component is included in the RGB signalswhen both of the value of the R signal and the value of the G signal arelarger than the value of the B signal.

The color component separation and detection instrument 101 outputs 1when the yellow color component is included in the RGB signals, and itoutputs 0 when the yellow color component is not included in the RGBsignals. Then, the output of the color component separation anddetection instrument 101 is inputted into the second selectioninstrument 106.

On the other hand, the first signal level conversion processinginstrument 102 inputs the B signal among the RGB signals inputted intothe display apparatus 112, and performs the conversion of lowering asignal level of a blue color which is a complementary color of theyellow color component. In other words, the first signal levelconversion processing instrument 102 performs the conversion ofincreasing saturation when the yellow color component is included in theRGB signals inputted into the display apparatus 112.

FIG. 2(a) shows the conversion processing which the first signal levelconversion processing instrument 102 performs to the B signal. Thus, thehorizontal axis of FIG. 2(a) shows the value of the B signal inputtedinto the first signal level conversion processing instrument 102, andthe vertical axis shows the value of the B signal after the first signallevel conversion processing instrument 102 performs the conversionprocessing. The first signal level conversion processing instrument 102has stored beforehand a conversion table for performing the conversionprocessing shown in FIG. 2(a), and performs the conversion processing ofFIG. 2(a) using the conversion table. In addition, although it wasexplained that the first signal level conversion processing instrument102 performed the conversion processing shown in FIG. 2(a) using theconversion table, it is not limited to this. For example, the conversionprocessing of FIG. 2(a) may be performed using a method other than theconversion table, such as performing the conversion processing shown inFIG. 2(a) by data processing by hardware or software.

Apparently from FIG. 2(a), when the value of the B signal inputted intothe first signal level conversion processing instrument 102 is smallerthan a predetermined value, the value of the B signal outputted from thefirst signal level conversion processing instrument 102 is set at 0.Then, when the value of the B signal inputted into the first signallevel conversion processing instrument 102 is larger than thepredetermined value, the value of the B signal outputted from the firstsignal level conversion processing instrument 102 is set at a valuelarger than 0, but it is set at a value smaller than the value of Bsignal inputted into the first signal level conversion processinginstrument 102.

In this way, since the first signal level conversion processinginstrument 102 converts the value of the B signal inputted as shown inFIG. 2(a), the value of the B signal in the RGB signals outputted fromthe first signal level conversion processing instrument 102 becomessmall in comparison with the RGB signals at the time of an input. This Bsignal outputted from the first signal level conversion processinginstrument 102 is made a first B signal.

Thus, when the RGB signals inputted into the display apparatus 112include the yellow color component 32 as shown in FIG. 5, the RGBsignals are newly constituted by synthesizing the first B signal,outputted from the first signal level conversion processing instrument102, with the R signal and G signal inputted into the display apparatus112. The constituted RGB signals become signals where saturation isincreased in comparison with the RGB signals inputted into the displayapparatus 112, since the yellow color component 32 increases and thewhite color component 33 decreases. The color correction of increasingsaturation like this is equivalent to an example of the first colorcorrection of the present invention, and let these RGB signals, wheresaturation increases, be first RGB signals, and it is equivalent to anexample of the first chrominance signal of the present invention.

In addition, the second signal level conversion processing instrument103 performs the conversion of increasing a signal level of a bluecolor, which is a complementary color of the yellow color component, tothe B signal among the RGB signals inputted into the display apparatus112. In other words, the second signal level conversion processinginstrument 103 performs the conversion of increasing a white colorcomponent when the yellow color component is included in the RGB signalsinputted into the display apparatus 112.

FIG. 2(b) shows the conversion processing which the second signal levelconversion processing instrument 103 performs to the B signal. Thus, thehorizontal axis of FIG. 2(b) shows the value of the B signal inputtedinto the second signal level conversion processing instrument 103, andthe vertical axis shows the value of the B signal after the secondsignal level conversion processing instrument 103 performs theconversion processing. The second signal level conversion processinginstrument 103 has stored beforehand a conversion table for performingthe conversion processing shown in FIG. 2(b), and performs theconversion processing of FIG. 2(b) using the conversion table. Inaddition, although it is explained that the second signal levelconversion processing instrument 103 performs the conversion processingshown in FIG. 2(b) using the conversion table, it is not limited tothis. For example, the conversion processing of FIG. 2(b) may beperformed using a method other than the conversion table, such asperforming the conversion processing shown in FIG. 2(b) by dataprocessing by hardware or software.

Since the second signal level conversion processing instrument 103converts the value of the B signal inputted as shown in FIG. 2(b), thevalue of the B signal in the RGB signals outputted from the secondsignal level conversion processing instrument 103 becomes large incomparison with the B signals at the time of an input. This B signaloutputted from the second signal level conversion processing instrument103 is made a second B signal.

Thus, when the RGB signals inputted into the display apparatus 112include the yellow color component 32, when RGB signals are newlyconstituted by synthesizing the second B signal, outputted from thesecond signal level conversion processing instrument 103, with the Rsignal and G signal inputted into the display apparatus 112, theconstituted RGB signals become signals where the white color componentincreases in comparison with the RGB signals inputted into the displayapparatus 112. In addition, the color correction of increasing the whitecolor component is equivalent to an example of the second colorcorrection of the present invention, and let these RGB signals, wherethe white color component increases, be second RGB signals, and it isequivalent to an example of the second chrominance signal of the presentinvention. Moreover, the level conversion of the B signal level by thefirst signal level conversion instrument 102 and second signal levelconversion instrument 103 is equivalent to an example of the colorcorrection step of the present invention.

The switching signal generation instrument 104 generates a switchingsignal using the dot clock, horizontal synchronizing signal, andvertical synchronizing signal for determining the timing when the RGBdisplay element driving instrument 110 and white display element drivinginstrument 108 of the display apparatus 112 drives the RGB display unit111 and white display unit 109, and outputs it to the first selectioninstrument 105. This switching signal is a signal of taking a value ofeither 1 or 0. In addition, the operation of the switching signalgeneration instrument 104 will be described later.

The first selection instrument 105 selects the first B signal outputtedfrom the first signal level conversion processing instrument 102 whenthe value of the switching signal outputted from the switching signalgeneration instrument 104 is 1, outputs it to the second selectioninstrument 106, selects the second B signal outputted from the secondsignal level conversion processing instrument 103 when the value of theswitching signal is 0, and outputs it to the second selection instrument106.

When the value of the signal which the color component separation anddetection instrument 101 outputs is 1, that is, when the yellow colorcomponent is included, the second selection instrument 106 selects thefirst or second B signal outputted from the first selection instrument105, and outputs it to the RGB display element driving instrument 110and white color component detection instrument 107. In addition, whenthe value of the signal which the color component separation anddetection instrument 101 outputs is 0, that is, when the yellow colorcomponent is not included, the second selection instrument 106 outputsthe B signal among the RGB signals, inputted into the display apparatus112, without conversion processing to the RGB display element drivinginstrument 110 and white color component detection instrument 107. ThisB signal outputted without conversion processing is made a third Bsignal. Moreover, let RGB signals, which are constituted of this Bsignal, which is not given the conversion processing, and the R signaland G signal, which are inputted into the display apparatus 112, bethird chrominance signals, and it is equivalent to an example of thechrominance signals of the present invention which are not given thecolor correction. In addition, the selection of the first B signal orsecond B signal by the switching signal mentioned above, and theselection of the first B signal, second B signal or third B signal bythe second selection instrument 106 is equivalent to an example of thecontrol step of the present invention.

Thus, the R signal and G signal which are inputted into the displayapparatus 112, and one of the first to third B signals outputted fromthe second selection instrument 106 are inputted into the RGB displayelement driving instrument 110 and white color component detectioninstrument 107. Then, the white color component detection instrument 107and RGB display element driving instrument 110 processes these R signal,G signal, and B signal as new RGB signals.

In addition, the operation of the white color component detectioninstrument 107, white display element driving instrument 108, whitedisplay unit 109, RGB display element driving instrument 110, and RGBdisplay unit 111 is the same as that of what were explained in thebackground art.

Thus, an image is displayed on a display screen (it is equivalent to anexample of the displaying step of the present invention).

By the way, the switching signal which the switching signal generationinstrument 104 outputs, for example, such a signal that the value of theswitching signal becomes 1 in a pixel adjacent to a certain pixel in ahorizontal direction when the value of the switching signal is 1 to thecertain pixel, the value of the switching signal becomes 0 in a furtheradjacent pixel horizontally, the value of the switching signal becomes 0in a still further adjacent pixel horizontally, and the value of theswitching signal becomes 1 in a further adjacent pixel horizontally.That is, when attention is paid to a horizontal pixel row, the switchingsignal takes 0 and 1 every two dot clocks for determining the timing ofdisplay every pixel. Similarly, when attention is paid to a verticalpixel column, the switching signal takes 0 and 1 every two horizontalperiods.

Hence, as shown in FIG. 8, yellow pixels 115 where the first RGB signalsare displayed, and white pixels 116 where the second RGB signals aredisplayed are alternately displayed in a checkered pattern with a2-pixels V×2-pixels H region as a block in a region of the displayscreen where the yellow color component is included in the inputted RGBsignals, that is, a region of the display screen where a plurality ofpixels having a yellow color component in the inputted RGB signals existadjacently.

In this way, the display apparatus 112 gives height difference insaturation to the region of the screen by performing display every pixelof the region in the region of the display screen, where the yellowcolor component is included in the inputted RGB signals, using either ofthe RGB signals where saturation is increased, and the second RGBsignals where the white color component is increased.

Hence, for example, bright yellow (yellow with low saturation), that is,pastel yellow is displayed with the yellow pixels 115 whose saturationis increased more, and the white pixels 116 where the white colorcomponent is increased more. Hence, it will be felt to human eyes by thestorage effect of human eyes that bright yellow (yellow with lowsaturation), that is, pastel yellow is displayed.

Further, since it is possible to increase the brightness of an imageportion by displaying bright yellow (yellow with low saturation), thatis, pastel yellow by the alternating display with the yellow whosesaturation is increased more, and the yellow where the white colorcomponent is increased more, even if the image portion being surroundedby white or being adjacent to white, it is possible to decrease thesense of incongruity that visible color appears differently such as thepastel yellow image portion seeming greenish and the like.

In addition, although bright yellow (yellow with low saturation), thatis, pastel yellow is expressed by the alternating display of yellowpixels 115 and white pixels 116 in a checkered pattern with a 2-pixelsV×2-pixels H region as a block in a region of the display screen wherethe yellow color component is included in the inputted RGB signals inFIG. 8, an equivalent effect can be obtained also by temporallyalternating display. That is, when a certain pixel is displayed in theyellow pixel 115, it is possible to perform display in the white pixel116 in the following frame.

That is, also when the first RGB signals corresponding to the yellowpixel 115, and the second RGB signals corresponding to the white pixel116 are switched and displayed every frame, it is possible to decreasethe sense of incongruity that visible color appears differently asmentioned above. Thus, it is equivalent to an example of the control ofthe present invention to switch and display the first RGB signals andsecond RGB signals temporally.

Next, as mentioned above, the switching signal generation instrument 104will be explained.

FIG. 9 shows the structure of the switching signal generation instrument104. The switching signal generation instrument 104 is constituted of afrequency divider 120, a frequency divider 121, a ½ frequency divider122, and calculation instrument 153.

The frequency divider 120 is the instrument which repeats twice the½-frequency dividing of a dot clock signal 117 inputted for the whitedisplay element driving instrument 108 and RGB display element drivinginstrument 110 to determine the timing of display every pixel, andoutputs a pixel alternating signal 123.

The frequency divider 121 is the instrument which repeats twice the½-frequency dividing of a horizontal synchronizing signal 118 inputtedfor the white display element driving instrument 108 and RGB displayelement driving instrument 110 to determine the timing of display everyhorizontal period, and outputs a line alternating signal 124.

The ½ frequency divider 122 is the instrument which performs thefrequency dividing of a vertical synchronizing signal 119 inputted forthe white display element driving instrument 108 and RGB display elementdriving instrument 110 to determine the timing of display every frame,and outputs a frame alternating signal 125.

The calculation instrument 153 is the instrument which obtains theexclusive OR of the pixel alternating signal 123, line alternatingsignal 124, and frame alternating signal 125, and outputs the obtainedexclusive OR as a switching signal 126.

Thus, the dot clock signal 117 is inputted into the frequency divider120, the frequency divider 120 repeats twice the ½-frequency dividingusing the dot clock signal 117, and outputs the pixel alternating signal123.

In addition, the horizontal synchronizing signal 118 is inputted intothe frequency divider 120 and frequency divider 121. The frequencydivider 120 is reset in the initial state in the timing when thehorizontal synchronizing signal 118 is inputted. Furthermore, thefrequency divider 121 repeats twice the ½-frequency dividing using thehorizontal synchronizing signal 118, and outputs the line alternatingsignal 124.

In addition, the vertical synchronizing signal 119 is inputted into thefrequency divider 121 and the ½ frequency divider 122. The frequencydivider 121 is reset in the initial state when the verticalsynchronizing signal 119 is inputted. Moreover, the ½ frequency divider122 performs the ½-frequency dividing of the vertical synchronizingsignal 119, and outputs the frame alternating signal 125.

The calculation instrument 153 inputs the pixel alternating signal 123,line alternating signal 124, and frame alternating signal 125, obtainsthe exclusive OR of them, and outputs it as the switching signal 126.

Since the frequency divider 120 and the frequency divider 121 repeat the½-frequency dividing twice using the dot clock signal 117 and horizontalsynchronizing signal 118 respectively, the switching signal 126expresses the checkered pattern with a 2-pixels V×2-pixels H region as ablock.

Since the first B signal or second B signal is switched and selectedevery two pixel units by the first selection instrument 105 using theswitching signal generation instrument 104 of FIG. 9, the firstchrominance signals or second chrominance signals are displayed in turnspatially every two pixel units in a region, where the yellow colorcomponent is contained, in the display screen.

Moreover, when attention is paid to a specific pixel, when the yellowcolor component is contained in the display screen, the firstchrominance signals and second chrominance signals are switched anddisplayed every frame.

FIG. 10 shows an example of an output at the time of using the switchingsignal 126. A display region 160 is a region including pastel yellowpixels 114, a display region 161 is a display region at the time of acertain frame displayed using the switching signal 126, and a displayregion 162 is a display region at the time of the next frame of thedisplay region 161.

As shown in FIG. 10, the yellow pixels 115 and white pixels 116 arealternately displayed in the checkered pattern with a 2-pixelsV×2-pixels H region as a block in the display region 161 and displayregion 162, and when attention is paid to a specific pixel, the yellowpixel 115 and white pixel 116 are switched and displayed in the displayregion 161 and display region 162.

In addition, in this third embodiment, when attention is paid to aspecific pixel, the yellow pixel 115 and white pixel 116 were switchedand displayed every frame, but in the case of the interlace mode, it maybe performed per field. For example, when one frame is displayed with anodd number field and an even number field, the switching of a specificpixel is performed every two fields.

In addition, as an example of control of a present invention, in thisthird embodiment, the control of making the yellow pixels 115 and whitepixels 116 displayed as a checkered pattern with a 2-pixels V×2-pixels Hregion as a block by switching the first B signal and second B signalevery two dot clocks and every two horizontal periods was shown.

However, a checkered pattern with a 2-pixels H region as a block may besufficient instead of the 2-pixels V×2-pixels H region, but in thatcase, selection is performed by switching the first B signal and secondB signal every two horizontal periods. The output result in this case isshown in FIG. 11. A display region 163 is a region including pastelyellow pixels 114, a display region 164 is a display region at the timeof a certain frame displayed using a switching signal of switching thefirst B signal and second B signal every two horizontal periods, and adisplay region 165 is a display region at the time of the next frame ofthe display region 164. As shown in FIG. 11, the yellow pixels 115 andwhite pixels 116 are alternately displayed in the checkered pattern witha 2-pixels H region as a block in the display region 164 and displayregion 165, and when attention is paid to a specific pixel, the yellowpixel 115 and white pixel 116 are switched and displayed in the displayregion 164 and display region 165.

Further, a checkered pattern with a 2-pixels V region as a block may besufficient, but in that case, selection is performed by switching thefirst B signal and second B signal every two dot clocks. Moreover, itmay be sufficient to switch the first B signal and second B signal so asto form the checkered pattern with a two-or-more pixels region as ablock besides every two pixels.

In addition, it may be two pixels or more as well as 2-pixels V×2-pixelsH.

As mentioned above, according to this third embodiment, even if a brightyellow (yellow with low saturation), that is, pastel yellow displayportion being surrounded by white or being adjacent to white, it ispossible to decrease the sense of incongruity that visible color appearsdifferently such as the pastel yellow image portion seeming greenish andthe like.

In addition, when a display apparatus is a one-chip DLP projector, fourcolors of RGBW are temporally switched and displayed in one pixel of ascreen with being synchronized with a color wheel. Although thistemporal switching is performed also in a PDP or the like, switchingtiming (PWM waveform) may be generally changed depending on a locationof a pixel so as to express smooth gradient. For example, if alternationis performed every field or frame in the checkered pattern whichperforms alternation every dot clock and every horizontal period, thePWM waveform may differ between fields or frames. As a result, since a ½component of a field or frame frequency which constitutes the PWMwaveform may become large, it may become a flicker. It is possiblefurther to suppress the occurrence of such a phenomenon by performingthe switching every two dot clocks or every two horizontal periods.

Furthermore, although the case where chrominance signals displayed onlyin the pastel yellow 114 as shown in the display region 160 of FIG. 10were described in this third embodiment, the case where the chrominancesignals which do not include the yellow color component are includedwill be also described below. In addition, as the chrominance signalswhich do not include the yellow color component, black will be mentionedas an example and described.

A display region 166 of FIG. 12 shows a display region including a smallnumber of black pixels 169 in a plurality of pastel yellow pixels 114.Moreover, a display region 167 is a display region at the time of acertain frame which displays chrominance signals of being displayed likethe display region 166 is displayed by the display device 112.Furthermore, a display region 168 shows a display region at the time ofthe next frame of the display region 167.

As to a plurality of chrominance signals displayed on this displayregion 166, the first B signal or second B signal is selected by thefirst selection instrument 105 in turn, and as to the black signal whichdoes not include a yellow color component, the third B chrominancesignal which is not given correction is selected by the second selectioninstrument 106, which are combined with the R signal and G signal, andare displayed.

Here, the selection of the first or second B signal by the firstselection instrument is performed every two pixel units, and this isalso performed when the third B signal is selected and displayed by thesecond selection instrument 106. Therefore, assuming that there is noblack pixel 169 temporarily and all the chrominance signals displayed inthe display region 167 include the yellow color component as shown inthe display region 167, the display device 112 displays the yellowpixels 115 and white pixels 116 in turn, and displays the black pixels169 as it is. Controlling like this display region 167 is equivalent toan example of the control of the present invention. In addition,although it was explained in this third embodiment that RGB signals wereinputted into the display apparatus 112, it is not limited to this, butsignals which express colors except RGB signals may be inputted.

Furthermore, although the display apparatus 141 performs the processing,which decreases the sense of incongruity of yellow appearance, in thisthird embodiment, it is also possible to perform the processing whichdecreases the sense of incongruity of magenta or cyan.

Moreover, although the conversion which the first signal levelconversion processing instrument 102 gives to a blue signal is linearconversion at a predetermined intensity level or higher as shown in FIG.2(a) in this third embodiment, nonlinear conversion is acceptable. Inshort, the first signal level conversion processing instrument 102 hasonly to convert the B signal inputted into the first signal levelconversion processing instrument 102 so as to be a smaller value incomparison with the B signal at the time of an input.

In addition, in this third embodiment, although the conversion which thesecond signal level conversion processing instrument 103 gives to theblue signal is linear conversion up to the predetermined intensitylevel, it may be nonlinear conversion. In short, the second signal levelconversion processing instrument 103 has only to convert the B signalinputted into the first signal level conversion processing instrument102 so as to be a large value in comparison with the B signal at thetime of the input.

Embodiment 4

Next, a fourth embodiment will be described.

In the fourth embodiment, similarly to the second embodiment, a displayapparatus which can decrease the sense of incongruity that visible colorappears differently for not only bright yellow (yellow with lowsaturation), that is, pastel yellow, but also bright magenta (magentawith low saturation), that is, pastel magenta, and bright cyan (cyanwith low saturation), that is, pastel cyan seems differently even if itsimage portion is surrounded by white or is adjacent to white will beexplained.

FIG. 13 is a block diagram showing the structure of the displayapparatus 141 of the fourth embodiment.

The display apparatus 141 is constituted of color component separationand detection instrument 134, the switching signal generation instrument104, R signal level conversion processing instrument 135, G signal levelconversion processing instrument 136, B signal level conversionprocessing instrument 137, first selection instrument 138, secondselection instrument 139, third selection instrument 140, the whitecolor component detection instrument 107, the white display elementdriving instrument 108, the white display unit 109, the RGB displayelement driving instrument 110, and the RGB display unit 111.

The color component separation and detection instrument 134 is theinstrument which outputs a yellow color component detection signalshowing whether a yellow color component is included in the RGB signalsinputted, outputs a magenta color component detection signal showingwhether a magenta color component is included in the RGB signalsinputted, and outputs a cyan color component detection signal showingwhether a cyan color component is included in the RGB signals inputted.

The switching signal generation instrument 104 is equivalent to what wasdescribed in the third embodiment.

The R signal level conversion instrument 135 is the instrument whichperforms the first color correction of lowering a signal level of a redcolor, which is a complementary color of a cyan color component, to an Rsignal among the RGB signals inputted, and the second color correctionof increasing a red signal level, and outputs the R signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 104.

The G signal level conversion instrument 136 is the instrument whichperforms the first color correction of lowering a signal level of agreen color, which is a complementary color of a magenta colorcomponent, to an G signal among the RGB signals inputted, and the secondcolor correction of increasing a green signal level, and outputs the Gsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 104.

The B signal level conversion instrument 137 is the instrument whichperforms the first color correction of lowering a signal level of a bluecolor, which is a complementary color of a yellow color component, to aB signal among the RGB signals inputted, and the second color correctionof increasing a blue signal level, and outputs the B signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 104.

In addition, the B signal level conversion instrument 137 is equivalentto the first signal level conversion processing instrument 102, secondsignal level conversion processing instrument 103, and first selectioninstrument 105 of the display apparatus 112 of the third embodiment.

Furthermore, the R signal level conversion instrument 135 is equivalentto the case that, in the first signal level conversion processinginstrument 102, second signal level conversion processing instrument103, and first selection instrument 105 of the display apparatus 112 ofthe third embodiment, color correction equivalent to the colorcorrection which the first signal level conversion processing instrument102 and second signal level conversion processing instrument 103 aregiven to a blue color is given to a red color using a conversion tableoptimized to a red color.

Moreover, the G signal level conversion instrument 136 is equivalent tothe case that, in the first signal level conversion processinginstrument 102, second signal level conversion processing instrument103, and first selection instrument 105 of the display apparatus 112 ofthe third embodiment, color correction equivalent to the colorcorrection which the first signal level conversion processing instrument102 and second signal level conversion processing instrument 103 aregiven to a blue color is given to a green color using a conversion tableoptimized to a green color.

The first selection instrument 138 is the instrument which selects andoutputs either of the R signal outputted from the R signal levelconversion instrument 135, and the R signal among the RGB signalsinputted into the display apparatus 141 on the basis of a cyan colorcomponent detection signal, that is, the detection result of the cyancolor component of the color component separation and detectioninstrument 134.

The second selection instrument 139 is the instrument which selects andoutputs either of the G signal outputted from the G signal levelconversion instrument 136, and the G signal among the RGB signalsinputted into the display apparatus 141 on the basis of a magenta colorcomponent detection signal, that is, the detection result of the magentacolor component of the color component separation and detectioninstrument 134.

The third selection instrument 140 is the instrument which selects andoutputs either of the B signal outputted from the B signal levelconversion instrument 137, and the B signal among the RGB signalsinputted into the display apparatus 141 on the basis of a yellow colorcomponent detection signal, that is, the detection result of the yellowcolor component of the color component separation and detectioninstrument 134.

In addition, since the white color component detection instrument 107,white display element driving instrument 108, white display unit 109,RGB display element driving instrument 110, and RGB display unit 111 arethe same as those of what are explained in the background art,explanation is omitted.

In addition, an example of the color detection instrument of the presentinvention is equivalent to the color component separation and detectioninstrument 134 in this fourth embodiment. Moreover, an example of thecolor correction instrument of the present invention is equivalent to aportion excluding a portion equivalent to the first selection instrument105, described in the third embodiment, from the R signal levelconversion instrument 135, G signal level conversion instrument 136, andB signal level conversion instrument 137 in the fourth embodiment.Moreover, an example of the control instrument of the present inventionis equivalent to a portion equivalent to the switching signal generationinstrument 104, first selection instrument 138, second selectioninstrument 139, and third selection instrument 140 in this fourthembodiment, and the first selection instrument 105 described in thethird embodiment. Furthermore, an example of the display instrument ofthe present invention is equivalent to the white color componentdetection instrument 107, white display element driving instrument 108,white display unit 109, RGB display element driving instrument 110, andRGB display unit 111 in the fourth embodiment.

Moreover, an example of three primary colors of the present invention isequivalent to an R (red) color, a G (green) color, and a B (blue) colorin this fourth embodiment. An example of chrominance signals of thepresent invention is equivalent to RGB signals in this fourthembodiment, and an example of the predetermined color component of thepresent invention is equivalent to yellow, magenta, and cyan in thisfourth embodiment.

About the other points, since they are the same as those of the secondembodiment, explanation is omitted.

Next, an example of a display method of the present invention will bealso concurrently explained with the operation of such display apparatusof the fourth embodiment. In addition, detailed explanation of the samepoints as the second embodiment is omitted.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 141, such as a personal computer, DVD equipment,or a TV receiver are inputted into the color component separation anddetection instrument 134. In addition, the R signal among the RGBsignals inputted is inputted into the R signal level conversioninstrument 135 and first selection instrument 138, the G signal amongthe RGB signals inputted is inputted into the G signal level conversioninstrument 136 and second selection instrument 139, and the B signalamong the RGB signals inputted is inputted into the B signal levelconversion instrument 137 and third selection instrument 140.

The color component separation and detection instrument 134 outputs 1 tothe first selection instrument 138 as a cyan color component detectionsignal, when the cyan color component is included in the RGB signalsinputted, and outputs 0 to the first selection instrument 138 as thecyan color component detection signal when the cyan component is notincluded in the RGB signals inputted.

In addition, the color component separation and detection instrument 134outputs 1 to the second selection instrument 139 as a magenta colorcomponent detection signal, when the magenta color component is includedin the RGB signals inputted, and outputs 0 to the second selectioninstrument 139 as the magenta color component detection signal when themagenta component is not included in the RGB signals inputted.

In addition, the color component separation and detection instrument 134outputs 1 to the third selection instrument 140 as a yellow colorcomponent detection signal, when the yellow color component is includedin the RGB signals inputted, and outputs 0 to the third selectioninstrument 140 as the yellow color component detection signal when theyellow color component is not included in the RGB signals inputted. Thedetection of the cyan color, magenta color, and yellow color by thiscolor component separation and detection instrument 134 is equivalent toan example of the color detection step of the present invention.

On the other hand, the R signal level conversion instrument 135 performsthe first color correction of lowering a signal level of a red color,which is a complementary color of a cyan color component, to an R signalinputted, and the second color correction of increasing a red signallevel. Then, it outputs to the first selection instrument 138 the Rsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 104.

Then, the first selection instrument 138 selects the R signal outputtedfrom the R signal level conversion instrument 135 when the cyan colorcomponent detection signal outputted from the color component separationand detection instrument 134 is 1, that is, a cyan color component isincluded in the RGB signals which is inputted into the display apparatus141, and outputs it to the white color component detection instrument107 and RGB display element driving instrument 110. On the other hand,the first selection instrument 138 selects the R signal among the RGBsignals, which is inputted into the display apparatus 141, when the cyancolor component detection signal outputted from the color componentseparation and detection instrument 134 is 0, that is, a cyan colorcomponent is not included in the RGB signals which is inputted into thedisplay apparatus 141, and outputs it to the white color componentdetection instrument 107 and RGB display element driving instrument 110.

The G signal level conversion instrument 136 performs the first colorcorrection of lowering a signal level of a green color, which is acomplementary color of a magenta color component, to a G signalinputted, and the second color correction of increasing a green signallevel. Then, it outputs to the second selection instrument 139 the Gsignal which is given color correction by either color correction of thefirst color correction and second color correction on the basis of theswitching signal outputted from the switching signal generationinstrument 104.

Then, the second selection instrument 139 selects the G signal outputtedfrom the G signal level conversion instrument 136 when the magenta colorcomponent detection signal outputted from the color component separationand detection instrument 134 is 1, that is, a magenta color component isincluded in the RGB signals which is inputted into the display apparatus141, and outputs it to the white color component detection instrument107 and RGB display element driving instrument 110. On the other hand,the second selection instrument 139 selects the G signal among the RGBsignals, which is inputted into the display apparatus 141, when themagenta color component detection signal outputted from the colorcomponent separation and detection instrument 134 is 0, that is, amagenta color component is not included in the RGB signals which isinputted into the display apparatus 141, and outputs it to the whitecolor component detection instrument 107 and RGB display element drivinginstrument 110.

The B signal level conversion instrument 137 performs the first colorcorrection of lowering a signal level of a blue color, which is acomplementary color of a yellow color component, to a B signal inputted,and the second color correction of increasing a blue signal level. Then,it outputs to the third selection instrument 140 the B signal which isgiven color correction by either color correction of the first colorcorrection and second color correction on the basis of the switchingsignal outputted from the switching signal generation instrument 104.

Then, the third selection instrument 140 selects the B signal outputtedfrom the B signal level conversion instrument 137 when the yellow colorcomponent detection signal outputted from the color component separationand detection instrument 134 is 1, that is, a yellow color component isincluded in the RGB signals which is inputted into the display apparatus141, and outputs it to the white color component detection instrument107 and RGB display element driving instrument 110. On the other hand,the third selection instrument 140 selects the B signal among the RGBsignals, which is inputted into the display apparatus 141, when theyellow color component detection signal outputted from the colorcomponent separation and detection instrument 134 is 0, that is, ayellow color component is not included in the RGB signals which isinputted into the display apparatus 141, and outputs it to the whitecolor component detection instrument 107 and RGB display element drivinginstrument 110. Each first color correction and second color correctionby the R signal level conversion instrument 135, G signal levelconversion instrument 136, and B signal level conversion instrument,which are mentioned above, are equivalent to an example of the colorcorrection step of the present invention. Moreover, it is equivalent toan example of the control step of the present invention to select anyone of a signal which is given the first color correction, a signalwhich is given the second color correction, and an inputted signal ineach signal of an R signal, a B signal, and a G signal on the basis ofthe switching signal and the signal from the color component separationand detection instrument 134.

The operation of the white color component detection instrument 107,white display element driving instrument 108, white display unit 109,RGB display element driving instrument 110, and RGB display unit 111 isthe same as that of what were explained in the background art.

In this way, an image is displayed on a display screen.

Here, since the RGB signals including both a yellow color component anda magenta color component, RGB signals including both a yellow colorcomponent and a cyan component, and RGB signals including both a magentacomponent and a cyan component do not exist, two or more of the yellowcolor component detection signal, magenta color component detectionsignal, and a cyan color component detection signal never take 1. Thus,there is only either a case that all values of the yellow colorcomponent detection signal, magenta color component detection signal,and cyan color component detection signal become 0, or a case that anyone signal takes 1.

Hence, display is performed as follows by using the switching signalgeneration instrument 104 of FIG. 9 as the switching signal generationinstrument 104. Thus, a region, where the yellow color component,magenta color component, or cyan color component is included, in adisplay screen is alternately displayed, for example as a checkeredpattern or the like, which is constituted of the RGB signals wheresaturation is increased, and the RGB signals where the white colorcomponent is increased, with a 2-pixels V×2-pixels H region as a block,and when attention is paid to one pixel, it is also alternatelydisplayed with the RGB signals where saturation is increased everyframe, and the RGB signals where the white color component is increased.

In this way, alternating display is performed like a checkered patternor the like with a 2-pixels V×2-pixels H region as a block in a regionof the display screen where the yellow color component, magenta colorcomponent, or cyan color component is included in the inputted RGBsignals, that is, a region of the display screen where a plurality ofpixels having the yellow color component, magenta color component, orcyan color component in the inputted RGB signals exist adjacently.

In this way, height difference in saturation is given to a region of thescreen by performing display every pixel of the region in the region ofthe display screen, where the yellow color component, magenta colorcomponent, or cyan color component is included in the inputted RGBsignals, using either of the RGB signals where saturation is increased,and the RGB signals where the white color component is increased.

In addition, the region on a display screen where the yellow colorcomponent, magenta color component, or cyan color component is includedmay be alternately displayed, for example, as a checkered pattern or thelike with a 2-pixels V×2-pixels H region as a block, and alternatingdisplay may not be performed every frame. In addition, such a region maybe displayed in one frame with either of the RGB signals, wheresaturation is increased, and the RGB signals where the white colorcomponent is increased, and alternating display may be performed withthe RGB signals, where saturation is increased, and the RGB signals,where the white color component is increased, every frame.

However, in the case of displaying with either of the RGB signals wheresaturation is increased, and the RGB signals, where the white colorcomponent is increased, in one frame, and performing the alternatingdisplay with the RGB signals where saturation is increased, and the RGBsignals, where the white color component is increased, every frame, aflicker arises when the number of frames displayed in 1 second is small,and hence, it is necessary to enlarge sufficiently the number of framesdisplayed in 1 second. In addition, in this fourth embodiment, whenattention is paid to a specific pixel, the yellow pixel 115 and whitepixel 116 were switched and displayed every frame, but in the case ofthe interlace mode, it may be performed per field. For example, when oneframe is displayed with an odd number field and an even number field,the switching of a specific pixel is performed every two fields.

As mentioned above, in the third embodiment, even if a bright yellow(yellow with low saturation), that is, pastel yellow image portion beingsurrounded by white or being adjacent to white, it was possible todecrease the sense of incongruity that visible color appears differentlysuch as the pastel yellow image portion seeming greenish and the like.

In addition, in the fourth embodiment, it is possible to decrease thesense of incongruity that visible color appears differently, also aboutbright yellow (yellow with low saturation), that is, pastel yellow, orbright magenta (magenta with low saturation), that is, pastel magenta,and bright cyan (cyan with low saturation), that is, pastel cyan, evenif its image portion is surrounded by white or is adjacent to white.

In addition, although it was explained in this fourth embodiment thatthe sense of incongruity of appearance of yellow, magenta, and cyan wasdecreased, it is also possible to decrease the sense of incongruity ofappearance of two or one of these three colors. For example, whendecreasing the sense of incongruity of appearance of only magenta, it isnot necessary to provide the R signal level conversion instrument 135,first selection instrument 138, B signal level conversion instrument137, and third selection instrument 140.

Embodiment 5

Next, the fifth embodiment will be described.

In the fifth embodiment, a display apparatus will be explained which,even if a bright yellow (yellow with low saturation), that is, pastelyellow image portion being surrounded by white or being adjacent towhite, can decrease the sense of incongruity that visible color appearsdifferently such as the pastel yellow image portion seeming greenish andthe like by performing color correction according to whether a displayportion fulfills a predetermined condition.

FIG. 14 is a block diagram showing the structure of a display apparatus212 of the fifth embodiment.

The display apparatus 212 is constituted of color component separationand detection instrument 201, first signal level conversion processinginstrument 202, second signal level conversion processing instrument203, first switching signal generation instrument 204, first selectioninstrument 205, second selection instrument 206, white color componentdetection instrument 207, white display element driving instrument 208,a white display unit 209, RGB display element driving instrument 210, anRGB display unit 211, pattern detection instrument 213, and anarithmetic unit 214.

The color component separation and detection instrument 201 is theinstrument which performs the separation and detection of a yellow colorcomponent, when the yellow color component is included in RGB signalsinputted.

The first signal level conversion processing instrument 202 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of lowering a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The second signal level conversion processing instrument 203 is theinstrument which inputs a B signal among the RGB signals inputted, andperforms the conversion of increasing a signal level of a blue color,which is a complementary color of a yellow color component, to the Bsignal.

The first switching signal generation instrument 204 is the instrumentwhich outputs a signal for the first selection instrument 205 selectingeither the B signal outputted from the first signal level conversionprocessing instrument 202 or the B signal outputted from the secondsignal level conversion processing instrument 203.

The first selection instrument 205 is the instrument which selects andoutputs either the B signal outputted from the first signal levelconversion processing instrument 202 or the B signal outputted from thesecond signal level conversion processing instrument 203 on the basis ofthe signal outputted from the switching signal generation instrument204.

The second selection instrument 206 is the instrument which selects andoutputs either of the B signal outputted from the first selectioninstrument 205, and the B signal among the RGB signals inputted into thedisplay apparatus 212 on the basis of an output of the arithmetic unit214.

The pattern detection instrument 213 is the instrument which detectswhether an input signal displayed on a plurality of pixels fulfills thepredetermined condition.

The arithmetic unit 214 is the instrument which makes the detectionresult of the yellow color component of the color component separationand detection instrument 201, and the result of the pattern detectioninstrument 213 as an input, and performs logical operation.

In addition, since the white color component detection instrument 207,white display element driving instrument 208, white display unit 209,RGB display element driving instrument 210, and RGB display unit 211 arethe same as those of what are explained in the background art,explanation is omitted.

Furthermore, an example of the color detection instrument of the presentinvention is equivalent to the color component separation and detectioninstrument 201 in this fifth embodiment. Moreover, an example of thecolor correction instrument of the present invention is equivalent tothe first signal level conversion processing instrument and secondsignal level conversion processing instrument in this fifth embodiment.In addition, an example of the judging instrument of the presentinvention is equivalent to the pattern detection instrument 213 in thisfifth embodiment, and an example of the control instrument of thepresent invention is equivalent to the arithmetic unit 214, firstswitching signal generation instrument 204, first selection instrument,and second selection instrument 206 in this fifth embodiment.Furthermore, an example of the display instrument of the presentinvention is equivalent to the white color component detectioninstrument 207, white display element driving instrument 208, whitedisplay unit 209, RGB display element driving instrument 210, and RGBdisplay unit 211 of this fifth embodiment.

Moreover, the R (red) color, G (green) color, and B (blue) color of thisfifth embodiment are examples of the three primary colors of the presentinvention, the RGB signals of this fifth embodiment are examples of thechrominance signals of the present invention, and the yellow of thisfifth embodiment is an example of the predetermined color component ofthe present invention.

Next, an example of a display method of the present invention will bealso concurrently explained with the operation of the display apparatus,having the above-mentioned structure, in this fifth embodiment.

The RGB signals inputted from an apparatus, which displays an image onthe display apparatus 212, such as a personal computer, DVD equipment,or a TV receiver are inputted into the color component separation anddetection instrument 201 and pattern detection instrument 213. Inaddition, the B signal among the RGB signals inputted is inputted intothe first signal level conversion processing instrument 202, secondsignal level conversion processing instrument 203, and second selectioninstrument 206. Furthermore, the R signal and G signal among the RGBsignals inputted are inputted into the white color component detectioninstrument 207 and RGB display element driving instrument 210.

The color component separation and detection instrument 201 detectswhether the RGB signals which are inputted include the yellow colorcomponent (this is equivalent to an example of the color detection stepof the present invention).

An example of the RGB signals is shown in FIG. 5. The R signal whichexpresses red, the G signal which expresses green, and the B signalwhich expresses blue are signals which can take 256 kinds of values from0 to 255 respectively, and the larger this value is, the brighter coloris expressed. The green color component 31, yellow color component 32,and white color component 33 are included in the RGB signals of FIG. 5.

It is possible to perform the detection of the yellow color componentfrom the RGB signals, by detecting the case that both of a value of theR signal and a value of the G signal are larger than a value of the Bsignal. Thus, the yellow color component is included in the RGB signalswhen both of the value of the R signal and the value of the G signal arelarger than the value of the B signal.

The color component separation and detection instrument 201 outputs 1when the yellow color component is included in the RGB signals, and itoutputs 0 when the yellow color component is not included in the RGBsignals. Then, the output of the color component separation anddetection instrument 201 is inputted into the arithmetic unit 214.

The pattern detection instrument 213 outputs 1, when an input signaldisplayed on a plurality of pixels does not fulfill a predeterminedcondition, and it outputs 0 when fulfilling (it is equivalent to anexample of the decision step of the present invention). Then, the outputof the pattern detection instrument 213 is inputted into the arithmeticunit 214. In addition, the operation of the pattern detection instrument213 will be described later.

The arithmetic unit 214 outputs the AND of the detection result of theyellow color component of the color component separation and detectioninstrument 1, and the result of the pattern detection instrument 213,which is inputted into the second selection instrument 206.

On the other hand, the first signal level conversion processinginstrument 202 inputs the B signal among the RGB signals inputted intothe display apparatus 212, and performs the conversion of lowering asignal level of a blue color which is a complementary color of theyellow color component. In other words, the first signal levelconversion processing instrument 202 performs the conversion ofincreasing saturation when the yellow color component is included in theRGB signals inputted into the display apparatus 212.

FIG. 2(a) shows the conversion processing which the first signal levelconversion processing instrument 202 performs to the B signal. Thus, thehorizontal axis of FIG. 2(a) shows the value of the B signal inputtedinto the first signal level conversion processing instrument 202, andthe vertical axis shows the value of the B signal after the first signallevel conversion processing instrument 202 performs the conversionprocessing. The first signal level conversion processing instrument 202has stored beforehand a conversion table for performing the conversionprocessing shown in FIG. 2(a), and performs the conversion processing ofFIG. 2(a) using the conversion table. In addition, although it wasexplained that the first signal level conversion processing instrument202 performed the conversion processing shown in FIG. 2(a) using theconversion table, it is not limited to this. For example, the conversionprocessing of FIG. 2(a) may be performed using a method other than theconversion table, such as performing the conversion processing shown inFIG. 2(a) by data processing by hardware or software.

Apparently from FIG. 2(a), when the value of the B signal inputted intothe first signal level conversion processing instrument 202 is smallerthan a predetermined value, the value of the B signal outputted from thefirst signal level conversion processing instrument 202 is set at 0.Then, when the value of the B signal inputted into the first signallevel conversion processing instrument 202 is larger than thepredetermined value, the value of the B signal outputted from the firstsignal level conversion processing instrument 202 is set at a valuelarger than 0, but it is set at a value smaller than the value of Bsignal inputted into the first signal level conversion processinginstrument 202.

In this way, since the first signal level conversion processinginstrument 202 converts the value of the B signal inputted as shown inFIG. 2(a), the value of the B signal in the RGB signals outputted fromthe first signal level conversion processing instrument 202 becomessmall in comparison with the RGB signals at the time of an input. This Bsignal outputted from the first signal level conversion processinginstrument 202 is made a first B signal.

Thus, when the RGB signals inputted into the display apparatus 212include the yellow color component 32 as shown in FIG. 5, RGB signalsare newly constituted of the first B signal, outputted from the firstsignal level conversion processing instrument 202, and the R signal andG signal which are inputted into the display apparatus 212. Theconstituted RGB signals become signals where saturation is increased incomparison with the RGB signals inputted into the display apparatus 212,since the yellow color component 32 increases and the white colorcomponent 33 decreases. The color correction of increasing saturationlike this is equivalent to an example of the first color correction ofthe present invention, and let these RGB signals, where saturationincreases, be first RGB signals, which are equivalent to examples of thefirst chrominance signals of the present invention.

In addition, the second signal level conversion processing instrument203 performs the conversion of increasing a signal level of a bluecolor, which is a complementary color of the yellow color component, tothe B signal among the RGB signals inputted into the display apparatus212. In other words, the second signal level conversion processinginstrument 203 performs the conversion of increasing a white colorcomponent when the yellow color component is included in the RGB signalsinputted into the display apparatus 212.

FIG. 2(b) shows the conversion processing which the second signal levelconversion processing instrument 203 performs to the B signal. Thus, thehorizontal axis of FIG. 2(b) shows the value of the B signal inputtedinto the second signal level conversion processing instrument 203, andthe vertical axis shows the value of the B signal after the third signallevel conversion processing instrument 203 performs the conversionprocessing. The second signal level conversion processing instrument 203has stored beforehand a conversion table for performing the conversionprocessing shown in FIG. 2(b), and performs the conversion processing ofFIG. 2(b) using the conversion table. In addition, although it wasexplained that the second signal level conversion processing instrument203 performed the conversion processing shown in FIG. 2(b) using theconversion table, it is not limited to this. For example, the conversionprocessing of FIG. 2(b) may be performed using a method other than theconversion table, such as performing the conversion processing shown inFIG. 2(b) by data processing by hardware or software.

Since the second signal level conversion processing instrument 203converts the value of the B signal inputted as shown in FIG. 2(b), thevalue of the second B signal in the RGB signals outputted from thesecond signal level conversion processing instrument 203 becomes largein comparison with the B signals at the time of an input. Thus, when theRGB signals inputted into the display apparatus 212 include the yellowcolor component 32, RGB signals are newly constituted of the B signal,outputted from the second signal level conversion processing instrument203, and the R signal and G signal which are inputted into the displayapparatus 212. The constituted RGB signals become signals where thewhite color component increases in comparison with the RGB signalsinputted into the display apparatus 212. In addition, the B signaloutputted from the second signal level conversion processing instrument203 is made a second B signal. Furthermore, the color correction ofincreasing the white color component is equivalent to an example of thesecond color correction of the present invention, and let these RGBsignals, where the white color component increases, be second RGBsignals, which are equivalent to examples of the second chrominancesignals of the present invention. Moreover, the conversion of the Bsignal level by the first signal level conversion instrument 202 andsecond signal level conversion instrument 203 is equivalent to anexample of the color correction step of the present invention.

The first switching signal generation instrument 204 generates aswitching signal using the dot clock, horizontal synchronizing signal,and vertical synchronizing signal for determining the timing when theRGB display element driving instrument 210 and white display elementdriving instrument 208 of the display apparatus 212 drives the RGBdisplay unit 211 and white display unit 209, and outputs it to the firstselection instrument 205. This switching signal is a signal of taking avalue of either 1 or 0. In addition, the operation of the firstswitching signal generation instrument 204 will be described later.

The first selection instrument 205 selects the first B signal outputtedfrom the first signal level conversion processing instrument 202 whenthe value of the switching signal outputted from the first switchingsignal generation instrument 204 is 1, and outputs it to the secondselection instrument 206, and selects the second B signal outputted fromthe second signal level conversion processing instrument 203 when thevalue of the switching signal is 0, and outputs it to the secondselection instrument 206.

When the value of the signal which the arithmetic unit 214 outputs is 1,that is, when the yellow color component is included and thepredetermined condition is not fulfilled, the second selectioninstrument 206 selects the first or second B signal outputted from thefirst selection instrument 205, and outputs it to the RGB displayelement driving instrument 210 and white color component detectioninstrument 207.

When the value of the signal which the arithmetic unit 214 outputs is 0,that is, when the yellow color component is not included or thepredetermined condition is fulfilled, the second selection instrument206 outputs the B signal among the RGB signals, inputted into thedisplay apparatus 212, without conversion processing to the RGB displayelement driving instrument 210 and white color component detectioninstrument 207. This B signal outputted without conversion processing ismade a third B signal. Moreover, let RGB signals, which are constitutedof this B signal, which is not given the conversion processing, and theR signal and G signal, which are inputted into the display apparatus212, be third chrominance signals, which is an example of chroma signalswhich are not given the color correction of the present invention. Inaddition, the selection of the first B signal or second B signal by theswitching signal mentioned above, and the selection of the first Bsignal, second B signal or third B signal by the second selectioninstrument 206 are equivalent to an example of the control step of thepresent invention.

Thus, the R signal and G signal which are inputted into the displayapparatus 201, and one of the first to third B signals outputted fromthe second selection instrument 206 are inputted into the RGB displayelement driving instrument 210 and white color component detectioninstrument 207. Then, the white color component detection instrument 207and RGB display element driving instrument 210 process the R signals, Gsignal, and B signal as a new RGB signal.

In addition, the operation of the white color component detectioninstrument 207, white display element driving instrument 208, whitedisplay unit 209, RGB display element driving instrument 210, and RGBdisplay unit 211 is the same as that of what were explained in thebackground art.

As mentioned above, an image is displayed on a display screen.

By the way, the switching signal which the first switching signalgeneration instrument 204 outputs is, for example, such a signal thatthe value of the switching signal becomes 0 in a pixel adjacent to acertain pixel in a horizontal direction when the value of the switchingsignal is 1 to the certain pixel, and, the value of the switching signalbecomes 1 in a further horizontally adjacent pixel. Thus, when attentionis paid to a horizontal pixel row, the switching signal takes 0 and 1 inturn. Similarly, when attention is paid to a vertical pixel column, theswitching signal takes 0 and 1 in turn.

Hence, as shown in FIG. 15, yellow pixels 218 where the first RGBsignals are displayed, and white pixels 219 where the second RGB signalsare displayed will be alternately displayed (displayed in a checkeredpattern) in a region of the display screen where the yellow colorcomponent is included in the inputted RGB signals, that is, a region ofthe display screen where a plurality of pixels having a yellow colorcomponent in the inputted RGB signals exist adjacently.

In this way, the display apparatus 212 gives the height difference insaturation to the region of the display screen by performing displayevery pixel of the region in the region of the display screen, where theyellow color component is included in the inputted RGB signals, usingeither of the first RGB signals where saturation is increased, and thesecond RGB signals where the white color component is increased.

Hence, for example, bright yellow (yellow with low saturation), that is,pastel yellow is displayed with the yellow pixels 218 whose saturationis increased more, and the white pixels 219 where the white colorcomponent is increased more. Hence, it will be felt to human eyes by thestorage effect of human eyes that bright yellow (yellow with lowsaturation), that is, pastel yellow is displayed.

Further, since it is possible to increase the brightness of an imageportion by displaying bright yellow (yellow with low saturation), thatis, pastel yellow by the alternating display with the yellow whosesaturation is increased more, and the yellow where the white colorcomponent is increased more, even if the image portion being surroundedby white or being adjacent to white, it is possible to decrease thesense of incongruity that visible color appears differently such as thepastel yellow image portion seeming greenish and the like.

In addition, although bright yellow (yellow with low saturation), thatis, pastel yellow is expressed by the alternating display of the yellowpixels 218 and the white pixels 219 every pixel for a region of thedisplay screen where the yellow color component is included in theinputted RGB signals in FIG. 15, an equivalent effect can be obtainedalso by temporally alternating display. That is, when a certain pixel isdisplayed with the first RGB signals, it is possible to perform displaywith the second RGB signal in the following frame.

That is, also when the first RGB signals, and second RGB signals areswitched and displayed every frame temporally by switching the first Bsignal and second B signal every frame, it is possible to decrease thesense of incongruity that visible color appears differently as mentionedabove. In this way, it is equivalent to an example of the control of thepresent invention to switch and display the first RGB signals and secondRGB signals temporally.

Next, as mentioned above, the first switching signal generationinstrument 204 will be described.

The structural example of the first switching signal generationinstrument 204 is shown in FIG. 16(a). The first switching signalgeneration instrument 204 is constituted of a ½ frequency divider 220, a½ frequency divider 221, a ½ frequency divider 222, and calculationinstrument 231.

The ½ frequency divider 220 is the instrument which performs the½-frequency dividing of a dot clock signal 268 inputted for the whitedisplay element driving instrument 208 and RGB display element drivinginstrument 210 to determine the timing of display every pixel, andoutputs a pixel alternating signal 223.

The ½ frequency divider 221 is the instrument which performs the ½frequency dividing of a horizontal synchronizing signal 269 inputted forthe white display element driving instrument 208 and RGB display elementdriving instrument 210 to determine the timing of display everyhorizontal period, and outputs a line alternating signal 224.

The ½ frequency divider 222 is the instrument which performs the ½frequency dividing of a vertical synchronizing signal 270 inputted forthe white display element driving instrument 208 and RGB display elementdriving instrument 210 to determine the timing of display every frame,and outputs a frame alternating signal 225.

The calculation instrument 253 is the instrument which obtains theexclusive OR of the pixel alternating signal 223, line alternatingsignal 224, and frame alternating signal 225, and outputs the obtainedexclusive OR as a switching signal 226.

Thus, the dot clock signal 268 is inputted into the ½ frequency divider220, the ½ frequency divider 220 performs the frequency dividing of thedot clock signal 268, and outputs the pixel alternating signal 223.

In addition, the horizontal synchronizing signal 269 is inputted intothe ½ frequency divider 220 and frequency divider 221. The ½ frequencydivider 220 is reset in the initial state at the timing when thehorizontal synchronizing signal 269 is inputted. Furthermore, the ½frequency divider 221 performs the frequency dividing of the horizontalsynchronizing signal 269, and outputs the line alternating signal 224.

Moreover, the vertical synchronizing signal 270 is inputted into the ½frequency divider 221 and ½ frequency divider 222. The ½ frequencydivider 221 is reset in the initial state when the verticalsynchronizing signal 270 is inputted. In addition, the ½ frequencydivider 222 performs the ½-frequency dividing of the verticalsynchronizing signal 270, and outputs the frame alternating signal 225.

The calculation instrument 231 inputs the pixel alternating signal 223,line alternating signal 224, and frame alternating signal 225, obtainsthe exclusive OR of them, and outputs it as the switching signal 226.

Since the ½ frequency divider 220 and the ½ frequency divider 221perform the ½ frequency dividing of the dot clock signal 268 andhorizontal synchronizing signal 269 respectively, the switching signal226 becomes what expresses a checkered pattern every frame. Thus, theswitching signal 226 is a signal using the dot clock signal 268 inputtedso as to determine the timing of display every pixel.

Since the first B signal or second B signal is switched and selectedevery pixel by the first selection instrument 205 using the firstswitching signal generation instrument 204 of FIG. 16(a), the firstchrominance signals or second chrominance signals are displayed in turnspatially every pixel in a region, where the yellow color component iscontained, in the display screen.

Moreover, when attention is paid to a specific pixel, when the yellowcolor component is contained in the display screen, the firstchrominance signals and second chrominance signals are switched anddisplayed every frame.

An example of an output of the switching signal 226 is shown in FIG. 17.

A display region 233 is a region including pastel yellow pixels 232, adisplay region 234 is a display region at the time of a certain framedisplayed by the first switching signal generation instrument 204, and adisplay region 235 is a display region at the time of the next frame ofthe display region 234 displayed by the first switching signalgeneration instrument 204.

As shown in FIG. 17, the yellow pixels 236 and white pixels 237 arealternately displayed in the checkered pattern in the display region 234and display region 235, and when attention is paid to specific pixels,the yellow pixel 236 and white pixel 237 are switched and displayed inthe display region 234 and display region 235. Here, the yellow pixel236 is what the first RGB signals which is given the conversionprocessing so that saturation may increase are displayed, the whitepixel 237 is what the second RGB signals which is given the conversionprocessing so that a white color component may increase is displayed.

Moreover, the case where a display region contains a small number ofblack pixels 241 in a plurality of pastel yellow pixels 232 will be alsodescribed. A display region 261 of FIG. 18 shows a display regionincluding a small number of black pixels 241 in a plurality of pastelyellow pixels 232. In addition, a display region 262 is a display regionat the time of a certain frame which displays chrominance signals, whichare displayed like the display region 261, by the display apparatus 212.Moreover, a display region 263 shows a display region at the time of thenext frame of the display region 262.

As to a plurality of chrominance signals displayed on this displayregion 261, when the predetermined condition is not fulfilled, the firstB signal or second B signal is selected by the first selectioninstrument 205 in turn, and as to a black signal which does not includea yellow color component, the third B chrominance signal which is notgiven correction is selected by the second selection instrument 206,which is combined with the R signal and G signal, and is displayed.

Here, since the selection of the first or second B signal by the firstselection instrument is performed every pixel, this is also performedwhen the third B signal is selected and displayed by the secondselection instrument 206. Therefore, assuming that there is no blackpixel 241 temporarily and all the chrominance signals displayed in thedisplay region 261 include the yellow color component as shown in thedisplay region 262, the display device 212 displays the yellow pixels236 and white pixels 237 in turn, and displays the black pixels 241 asit is. Displaying like this display region 262 is equivalent to anexample of the control of the present invention.

In addition, FIG. 16(b) shows another structure of the first switchingsignal generation measure 204. The first switching signal generationinstrument 204 of FIG. 16(b) is constituted of a frequency dividers 227where two ½ frequency dividers are connected in series, a frequencydivider 228 where two ½ frequency dividers are connected in seriessimilarly to 227, a ½ frequency divider 229, and calculation instrument231.

The frequency divider 227 is the instrument which repeats twice the½-frequency dividing of the dot clock signal 268 inputted for the whitedisplay element driving instrument 208 and RGB display element drivinginstrument 210 to determine the timing of display every pixel, andoutputs it as the pixel alternating signal 223.

The frequency divider 228 is the instrument which repeats twice the½-frequency dividing of the horizontal synchronizing signal 269 inputtedfor the white display element driving instrument 208 and RGB displayelement driving instrument 210 to determine the timing of display everyhorizontal period, and outputs it as the line alternating signal 224.

The ½ frequency divider 222 is the instrument which performs the ½frequency dividing of the vertical synchronizing signal 270 inputted forthe white display element driving instrument 208 and RGB display elementdriving instrument 210 to determine the timing of display every frame,and outputs the frame alternating signal 225.

The calculation instrument 231 is the instrument which obtains theexclusive OR of the pixel alternating signal 223, line alternatingsignal 224, and frame alternating signal 225, and outputs the obtainedexclusive OR as a switching signal 230.

Thus, the dot clock signal 268 is inputted into the frequency divider227, the frequency divider 227 repeats twice the ½-frequency dividingusing the dot clock signal 268 inputted, and outputs a generated signalas the pixel alternating signal 223.

In addition, the horizontal synchronizing signal 269 is inputted intothe frequency divider 227 and frequency divider 228. The frequencydivider 227 is reset in the initial state at the timing when thehorizontal synchronizing signal 269 is inputted. In addition, thefrequency divider 228 repeats twice the ½-frequency dividing using thehorizontal synchronizing signal 269, and outputs the line alternatingsignal 224.

Furthermore, the vertical synchronizing signal 270 is inputted into thefrequency divider 228 and the ½ frequency divider 229. The frequencydivider 228 is reset in the initial state when the verticalsynchronizing signal 270 is inputted. In addition, the ½ frequencydivider 229 performs the ½-frequency dividing of the verticalsynchronizing signal 270, and outputs the frame alternating signal 225.

The calculation instrument 231 inputs the pixel alternating signal 223,line alternating signal 224, and frame alternating signal 225, obtainsthe exclusive OR of them, and outputs it as the switching signal 230.

An example of an output of the switching signal 230 is shown in FIG. 19.

A display region 238 is a region including the pastel yellow pixels 232,a display region 239 is a display region at the time of a certain framedisplayed by the first switching signal generation instrument 204, and adisplay region 240 is a display region at the time of the next frame ofthe display region 239 displayed by the first switching signalgeneration instrument 204.

As shown in FIG. 19, the yellow pixels 236 and white pixels 237 arealternately displayed in the checkered pattern with a 2-pixelsV×2-pixels H region as a block in the display region 239 and displayregion 240, and when attention is paid to a specific pixel, the yellowpixel 236 and white pixel 237 are switched and displayed in the displayregion 239 and display region 240.

In addition, in this fifth embodiment, when attention is paid to aspecific pixel, the yellow pixel 236 and white pixel 237 were switchedand displayed every frame, but in the case of the interlace mode, it maybe performed per field. For example, when one frame is displayed with anodd number field and an even number field, the switching of a specificpixel is performed every two fields.

Next, as mentioned above, the pattern detection instrument 213 will bedescribed, but before that, a problem at the time when not performingpattern detection will be described.

When an output of the second selection instrument 206 is display in thedisplay region 233 where a plurality of pixels having the pastel yellowpixel 232 as shown in FIG. 17 exist adjacently using the switchingsignal 226 of FIG. 16(a), the pastel yellow pixel 232 is converted intothe yellow pixel 236 and the white pixel 237, and the yellow pixel 236and white pixel 237 are alternately displayed in a checkered pattern asthe display region 234 and display region 235. Furthermore, since thedisplay region 234 and display region 235 alternate every frame, animage into which the yellow pixel 236 and white pixel 237 aresynthesized appears owing to a storage effect of human being's eyes.

On the other hand, FIG. 20 shows an example of displaying an output ofthe second selection instrument 206 in the display region 242, where acheckered pattern is constituted of the pastel yellow pixels 232 andblack pixels 241, using the switching signal 226 of FIG. 16(a). Inaddition, since the problem at the time when not performing patterndetection is described, the second selection instrument 206 selects thefirst B signal or second B signal from the first selection instrument205 when a predetermined color component is detected, and it selects thethird B signal, which is not given correction, when the predeterminedcolor component is not detected.

A display region 243 is a display region at the time of a certain framewhere an output of the second selection instrument 206 is displayedusing the switching signal 226, and a display region 244 is a displayregion at the time of the next frame of the display region 243.

As shown in FIG. 20, when pixels originally having the pastel yellowpixel 232 exist every one pixel, in a frame of the display region 243,all the pastel yellow pixels 232 are converted into the yellow pixels236, and the yellow pixels 236 and black pixels 241 are alternatelydisplayed in a checkered pattern. This is because the third chrominancesignals (black) which are not given the color correction are displayedbecause the third B signal which is not given the correction is selectedin the second selection instrument 206 since the chrominance signalscorresponding to the black pixel 241 does not include a yellow colorcomponent. Moreover, since the black pixel 241 does not have luminanceand saturation, that is, the display region 243 becomes a screen whichis constituted of only yellow pixels 236.

In addition, in a frame of the display region 244, all the pastel yellowpixels 232 are converted into the white pixels 237, and the white pixels237 and black pixels 241 are alternately displayed in a checkeredpattern. Thus, the display region 244 becomes a screen which isconstituted of only the white pixels 237.

Then, since the display region 243 and display region 244 alternateevery frame, a display region, which is constituted of only the yellowpixels 236, and a display region which is constituted of only whitepixels 237 alternate in a frame. In this case, since the whole displayregion is constituted of only the yellow pixels 236 or white pixels 237,it appears a flicker when frame alternating is performed.

In order to solve this problem, the pattern detection instrument 213detect whether a plurality of RGB signals displayed on a display regionfulfill a predetermined condition. This predetermined condition is, forexample, a case of spatial arrangement like a display region 242 shownin FIG. 20. Thus, it is a case that a pixel which was the pastel yellowpixel 232 is constituted of only the yellow pixel 236 or only the whitepixel 237 as a display result of the display apparatus 212 displaying.As is evident from this example, it is necessary according to the firstswitching signal generation instrument 204 to change the predeterminedcondition judged by the pattern detection instrument 213.

In addition, as for the example of being given the first switchingsignal generation instrument 204 of FIG. 16(a), the spatial arrangementthat a pixel which was the pastel yellow pixel 232 is constituted ofonly the yellow pixel 236 is not limited to the case that the pastelyellow pixel 232 and a pixel in which chrominance signals which do notinclude a yellow color component are displayed constitutes the checkeredpattern.

FIG. 21 shows a display region 245 where a part of pastel yellow pixels232 which constitute a checkered pattern is changed into the blackpixels. The display region 245 is a region including pastel yellowpixels 232, a display region 246 is a display region at the time of acertain frame where an output of the second selection instrument 206 isdisplayed using the switching signal 226 of FIG. 16(a), and a displayregion 247 is a display region at the time of the next frame of thedisplay region 246. As shown in the display region 246, the pixels whichwere the pastel yellow pixels 232 are constituted of only the yellowpixels 236. Also in this case, it appears a flicker when framealternating is performed.

As mentioned above, the case where the whole display region isconstituted of only the yellow pixels 236 or white pixels 237 except theblack pixels 241 is equivalent to an example of the predeterminedcondition of the present invention. Moreover, the predeterminedcondition of the present invention, that is, the case that thechrominance signals which do not include the above-mentioned colorcomponent are displayed without the above-mentioned color correction,and the chrominance signals including the above-mentioned colorcomponent are spatially alternately displayed with the above-mentionedfirst chrominance signals and the above-mentioned second chrominancesignals assuming that all the chrominance signals displayed on pixels ofthe above-mentioned predetermined region include the predetermined colorcomponent is, for example, in this fifth embodiment, a case as shown inthe display regions 243 and 244 of FIG. 20 and the display regions 246and 247 of FIG. 21 where the yellow pixels 236 and white pixels 237 arealternately displayed and the black chrominance signal is displayed asblack pixels 241 as it is, as shown in the display region 234 of FIG. 17in regard to the chrominance signals displayed in a predetermineddisplay region.

In addition, although the example that the predetermined condition isthe case that the pixels which were the pastel yellow pixels 232 wereconstituted of only the yellow pixels 236 like the examples of thedisplay regions 242 and 243 was cited, a small number of white pixels237 in comparison with the yellow pixels 236 may exist in the pixelswhich were the pastel yellow pixels 232.

In this case, in the display region at the time of a certain frame, acase that an area displayed as the yellow pixels 236 exists by 5% orlarger than an area displayed as the white pixels 237 is made thepredetermined condition. The figure of this 5% is an actual measurementobtained by measurement. In addition, a case that an area displayed asthe white pixels 237 exists by 5% or larger than an area displayed asthe yellow pixels 236 can be also made the predetermined condition. Suchpredetermined conditions are equivalent to examples of the predeterminedcondition of the present invention.

In addition, a specific pixel alternates into the yellow pixel 236 andwhite pixel 237 every frame by the ½ frequency divider 222 of the firstswitching signal generation instrument 204. It was described that, whenthe display region 242 fulfilled the predetermined condition at the timeof performing this alternation, a flicker arose. However, although aflicker does not arise since the yellow pixels 236 and white pixels 237do not alternate every field when there is no ½ frequency divider 222 ofthe first switching signal generation instrument 204 of FIG. 16(a), itis not possible to sufficiently obtain the above-mentioned effect ofincreasing the brightness of an image portion by displaying the pastelyellow pixels 232 in the alternating display of the yellow pixels 236whose saturation is increased more, and the white pixels 237 where thewhite color component is increased more.

For example, when an output of the first selection instrument 205 isdisplayed in the display region 242, where a checkered pattern isconstituted of the pastel yellow pixels 232 and black pixels 241 asshown in FIG. 20, using the first switching signal generation instrument204 of FIG. 16(a) in the structure without the ½ frequency divider 222,a display region is constituted of the yellow pixels 236 and blackpixels 241 like the display region 243 of FIG. 20. That is, the pastelyellow pixel 232 is converted only into the yellow pixel 236 whosesaturation is increased more, and the brightness of its image portiondoes not increase.

Thus, as the examples of the display regions 242 and 243, when pixelswhich were the pastel yellow pixels 232 are constituted of only theyellow pixels 236, a display area of the yellow pixels 236 exists by 5%or larger than a display area of the white pixels 237, and the yellowpixels 236 and white pixels 237 do not alternate every field, thebrightness of its image portion does not increase.

In addition, when an output of the first selection instrument 205 isdisplayed in the display region 242, where a checkered pattern isconstituted of the pastel yellow pixels 232 and black pixels 241 asshown in FIG. 20, using the first switching signal generation instrument204 of FIG. 16(a) in the structure without the ½ frequency divider 222,the display region 242 may be also converted into a display region whichis constituted of the white pixels 237 and black pixels 241 like thedisplay region 244. In this case, the pastel yellow pixels 232 areconverted only into the white pixels 237 where the white color componentis increased more, and the decrease of saturation of its image portionbecomes large.

Thus, as the examples of the display regions 242 and 244, when pixelswhich were the pastel yellow pixels 232 are constituted of only thewhite pixels 237, a display area of the white pixels 237 exists by 5% orlarger than a display area of the yellow pixels 236, and the yellowpixels 236 and white pixels 237 do not alternate every field, thedecrease of saturation of its image portion is large.

In order to prevent a flicker arisen the decrease of brightness orsaturation, or arisen at the time of frame alternation as mentionedabove, it is detected whether a predetermined condition is fulfilled bythe pattern detection instrument 213.

Hereafter, an embodiment of the pattern detection instrument 213 will bedescribed.

An example of detecting a checkered pattern as a predetermined conditionwill be shown using FIG. 22, FIG. 23, and FIG. 24. As shown in FIG. 22,the checkered pattern is constituted of black pixels 248, 250, and 252and pastel yellow pixels 249, 251, and 253. An example of the patterndetection instrument 213 which detects whether the pastel yellow pixel253 coincides with a checkered pattern will be described. It is assumedthat RGB signals of each pixel of black and pastel yellow are (R, G,B)=(R1, G1, B1) for 248, (R, G, B)=(R2, G2, B2) for 249, (R, G, B)=(R3,G3, B3) for 250, (R, G, B)=(R4, G4, B4) for 251, (R, G, B)=(R5, G5, B5)for 252, (R, G, B)=(R6, G6, B6) for 253.

A block structural diagram of the pattern detection instrument 213 isshown in FIG. 23. The pattern detection instrument 213 is constituted ofline memory 254, eleven flip-flops (255, 256, and the like), and a firstarithmetic unit 257. All of the above-mentioned eleven flip-flops supplythe dot clock signal 268, which is a dot clock signal for the whitedisplay element driving instrument 208 and RGB display element drivinginstrument 210 to determine the timing of display every pixel, as abasic clock.

It is assumed that (R, G, B)=(R6, G6, B6) be inputted as an inputsignal. The (R6, G6, B6) are inputted into the line memory 254. R, G,and B signals before one line are outputted from the line memory 254.Those data are (R, G, B)=(R3, G3, B3). In addition, the signal R3 isinputted into the flip-flop 255, and the signal R2 before one pixel isoutputted from the flip-flop 255. Similarly, the signal R2 is inputtedinto the flip-flop 256, and the signal R1 before one pixel is outputtedfrom the flip-flop 256. Similarly, R4 and R5 signals are outputted fromflip-flops. These R1, R2, R3, R4, R5, and R6 signals are inputted intothe first arithmetic unit 257. Similarly, the G1, G2, G3, G4, G5, G6,B1, B2, B3, B4, B5, and B6 signals are also inputted into the firstarithmetic unit 257.

A flow chart of data processing performed by the arithmetic unit 257 isshown in FIG. 24. When conditional expression |R1-R3|<Threshold 1 istrue, it means that values of R1 and R3 are nearly equal. Similarly,when |G1-G3|<Threshold 1 and |B1-B3|<Threshold 1 are also true, it meansthat (R, G, B)=(R1, G1, B1) and (R, G, B)=(R3, G3, B3) have similarsignal values. That is, it means that signal values of a black pixel 248and a black pixel 250 are nearly equal. Hence, all of the followings aretrue:

|R1-R3|<Threshold 1, |G1-G3|<Threshold 1, |B1-B3|<Threshold 1

|R3-R5|<Threshold 1, |G3-G5|<Threshold 1, |B3-B5|<Threshold 1

|R2-R4|<Threshold 1, |G2-G4|<Threshold 1, |B2-B4|<Threshold 1

|R4-R6|<Threshold 1, |G4-G6|<Threshold 1, |B4-B6|<Threshold 1,

it means that colors of the black pixels 248 and 250, black pixels 250and 252, pastel yellow pixels 249 and 251, and pastel yellow pixels 251and 253 are similar, respectively.

In addition, when |R1-R2|<Threshold 2 is true, it means that values ofR1 and R2 nearly equal. Hence, any one of |R1-R2|<Threshold 2,|G1-G2|<Threshold 2, and |B1-B2|<Threshold 2 is false, it means thatcolors of the black pixel 248 and pastel yellow pixel 249 differ. Hence,all of the followings are true:

|R1-R3|<Threshold 1, |G1-G3|<Threshold 1, |B1-B3|<Threshold 1

|R3-R5|<Threshold 1, |G3-G5|<Threshold 1, |B3-B5|<Threshold 1

|R2-R4|<Threshold 1, |G2-G4|<Threshold 1, |B2-B4|<Threshold 1

↑R4-R6|<Threshold 1, |G4-G6|<Threshold 1, |B4-B6|<Threshold 1,

and any one of the followings is false:

|R1-R2|<Threshold 2, |G1-G2|<Threshold 2, |B1-B2|<Threshold 2,

the pastel yellow pixel 253 is apart of a checkered pattern, and patterndetection result outputs 0.

When not fulfilling the above-mentioned conditions, the pastel yellowpixel 253 is not a part of the checkered pattern, and the patterndetection result outputs 1. For example, when |R1-R3|<Threshold 1 isfalse, red colors of pixels 248 and 250 differ and a checkered patternis not constituted. In addition, for example, all of the followings aretrue:

|R1-R3|<Threshold 1, |G1-G3|<Threshold 1, |B1-B3|<Threshold 1

|R3-R5|<Threshold 1, |G3-G5|<Threshold 1, |B3-B5|<Threshold 1

|R2-R4|<Threshold 1, |G2-G4|<Threshold 1, IB2-B4|<Threshold 1

|R4-R6|<Threshold 1, |G4-G6|<Threshold 1, |B4-B6|<Threshold 1,

and all of the followings are true:

|R1-R2|<Threshold 2, |G1-G2|<Threshold 2, |B1-B2|<Threshold 2,

all of colors of pixels 248, 249, 250, 251, 252, and 253 are similar,and a checkered pattern is not constituted.

In addition, although the example of detecting whether the pastel yellowpixel 253 was a part of a checkered pattern was described in this fifthembodiment, it is not limited to this, but it may be sufficient todetect whether pixels 248, 249, 250, 251, and 252 are a part of acheckered pattern. However, in that case, it is necessary to make thedelay amount of output result coincide with other signals in FIG. 14.

For example, in the flow chart of FIG. 24, when pattern detectioncoincides to detect that the pastel yellow pixel 251 is a part of acheckered pattern, it is necessary to delay an output of the colorcomponent separation and detection instrument 201, an output of thefirst selection instrument 205, a B signal of an input of the secondselection instrument 206, an R signal and a B signal of an input of thewhite color component detection instrument 207, and an R signal and an Bsignal of an input of the RGB display element driving instrument 210 bytwo clocks.

In addition, although the example of detecting whether the pastel yellowpixel was a part of a checkered pattern was described in this fifthembodiment, it is not limited to this, but it may be sufficient todetect whether it is a part of another pattern. For example, it may bealso sufficient to perform the pattern detection of the display region245 as shown in FIG. 21. However, in that case, in the case of acheckered pattern or a pattern of the display region 245 as shown inFIG. 21, pattern detection result is set at 0. That is, when inagreement with one of patterns, it is made for the second selectioninstrument 206 to output the third B signal which is not givencorrection.

Furthermore, although the example of performing frame alternation asfirst switching signal generation instrument was described in this fifthembodiment, it is also applicable to the above-mentioned case of notperforming the frame alternation. For example, when not performing theframe alternation in FIG. 20, an output of first selection instrumentbecomes the display region 243. In this case, the display region 243becomes low luminance in comparison with the display region 242, andhence, it does not become the correction to be intended. In addition,for example, when not performing the frame alternation in FIG. 20, anoutput of the first selection instrument becomes the display region 244.In this case, the display region 244 becomes low saturation incomparison with the display region 242, and hence, it does not becomethe correction to be intended. Hence, in such a case, when patternscoincide in the pattern detection instrument 213, the third B signal isoutputted from second selection instrument.

In addition, although a checkered pattern was mentioned as an example asan example of predetermined condition, and the pattern detection ofwhether six chrominance signals displayed on six pixels were a part ofthe checkered pattern was described in this fifth embodiment, it may bealso sufficient to detect whether all the chrominance signals displayedon the whole display region are a checkered pattern.

Moreover, when a case that anyone of an area displayed as the yellowpixels 236 and an area displayed as the white pixels 237 exists by 5% orlarger than another side is made a predetermined condition, the patterndetection instrument 213 has only to detect whether it is 5% or less ofthreshold from the amount of chrominance signals displayed as yellowpixels 236, and chrominance signals displayed as white pixels 237, whichare included in all the chrominance signals displayed on a displayregion.

In addition, although it was described in this fifth embodiment that RGBsignals were inputted into the display apparatus 212, it is not limitedto this, but signals of expressing colors other than the RGB signals maybe inputted.

Furthermore, although the display apparatus 212 performed the processingof decreasing the sense of incongruity of yellow appearance in thisfifth embodiment, it is also possible to perform the processing ofdecreasing the sense of incongruity of magenta or cyan.

Furthermore, although the conversion which the first signal levelconversion processing instrument 202 gives to a blue signal is linearconversion at a predetermined intensity level or higher as shown in FIG.2(a) in this fifth embodiment, nonlinear conversion is acceptable. Inshort, the first signal level conversion processing instrument 202 hasonly to convert B signal inputted into the first signal level conversionprocessing instrument 202 so as to become a signal whose value isreduced in comparison with the B signal at the time of an input.

Moreover, in this embodiment, although the conversion which secondsignal level conversion processing instrument 203 gave to the bluesignal was linear conversion up to the predetermined intensity level, itmay be nonlinear conversion. In short, the second signal levelconversion processing instrument 203 has only to convert the B signalinputted into the first signal level conversion processing instrument202 so as to be a large value in comparison with the B signal at thetime of an input.

Embodiment 6

Next, a sixth embodiment will be described.

In the sixth embodiment, a display apparatus will be explained which,even if a bright yellow (yellow with low saturation), that is, pastelyellow display portion being surrounded by white or being adjacent towhite, can decrease the sense of incongruity that visible color appearsdifferently such as the pastel yellow display portion seeming greenishand the like, and further, can decrease the sense of incongruity thatvisible color appears differently by changing color correctionprocessing even when the display portion does not fulfill apredetermined condition.

FIG. 25 is a structural diagram of the display apparatus in this sixthembodiment.

A display apparatus 260 of FIG. 25 is constituted of the color componentseparation and detection instrument 201, first signal level conversionprocessing instrument 202, second signal level conversion processinginstrument 203, first switching signal generation instrument 204, firstselection instrument 205, second selection instrument 206, white colorcomponent detection instrument 207, white display element drivinginstrument 208, white display unit 209, RGB display element drivinginstrument 210, RGB display unit 211, pattern detection instrument 213,second switching signal generation instrument 258, and third selectioninstrument 259.

The operation of the above-mentioned color component separation anddetection instrument 201, first signal level conversion processinginstrument 202, second signal level conversion processing instrument203, first switching signal generation instrument 204, first selectioninstrument 205, second selection instrument 206, white color componentdetection instrument 207, white display element driving instrument 208,white display unit 209, RGB display element driving instrument 210, andRGB display unit 211 is similar to the fifth embodiment, and hence,description is omitted.

The structure shown in FIG. 16(b) may be sufficient for the secondswitching signal generation instrument 258, which generates theswitching signal 230. The first switching signal generation instrument204 has the structure shown in FIG. 16(a) similarly to the fifthembodiment, and generates the switching signal 226. Moreover, the thirdselection instrument 259 selects the switching signal 226 when ‘1’ whichmeans that a predetermined condition is not fulfilled is inputted fromthe pattern detection instrument 213, and selects the switching signal230 when ‘0’ which means that a predetermined condition is fulfilled isinputted.

Hereinafter, the operation of the display apparatus 260 of this sixthembodiment will be described.

When the first selection instrument 5 is operated using the outputresult of the first switching signal generation instrument 204 when acheckered pattern is formed of the pastel yellow pixels 232 and blackpixels 241 whose pastel yellow display region is like 242 in FIG. 20, aflicker arises since it becomes the frame alternation of the displayregion 243 of FIG. 20, and the display region 244 of FIG. 20.

Then, when a checkered pattern is detected by the pattern detectioninstrument 213, its output is set at 0. Then, an output of the thirdselection instrument 259 serves as the switching signal 230 which is anoutput of the second switching signal generation instrument 258. A casewhere the switching signal 230 is used is shown in FIG. 26. A displayregion 264 is a display region at the time of a certain frame which isdisplayed using the switching signal 230, and a display region 265 is adisplay region at the time of the next frame of the display region 264.When displaying the display region 238 currently displayed only in thepastel yellow pixels 232 on the basis of the switching signal 230, theyellow pixels 236 and white pixels 237 are displayed in turn spatiallyevery two pixels as shown in FIG. 19.

Therefore, it is possible to avoid a flicker even if frame alternationis performed since the yellow pixels 236 and white pixels 237 aredisplayed on the display region 264 at the time of a certain frame evenif a pastel yellow display region is a checkered pattern like 242 inFIG. 26.

In addition, it is equivalent to an example of such control of thepresent invention of being spatially displayed in turn every two or morepixel units to make it displayed in turn every two pixels as mentionedabove. Moreover, it is not necessary to limit to “every two pixels”,but, in short, it has only to be able to make displayed so as to be ableto avoid a flicker.

Furthermore, the switching signal 226 is equivalent to an example of thefirst switching signal, and the switching signal 230 is equivalent to anexample of the second switching signal of the present invention.Moreover, the third selection instrument 259 is equivalent to an exampleof the switching signal selection instrument of the present invention.

In addition, the color detection instrument of the present invention isequivalent to the color component separation instrument 201 in thissixth embodiment, and the color correction instrument of the presentinvention is equivalent to the first signal level conversion processinginstrument 202 and second signal level conversion processing instrumentin this sixth embodiment. Moreover, the judging instrument of thepresent invention is equivalent to, for example, the pattern detectioninstrument 213 in this sixth embodiment. In addition, the control deviceof the present invention is equivalent to, for example, the firstswitching signal generation instrument 204, second switching signalgeneration instrument 258, first selection instrument 205, secondselection instrument 206, and third selection instrument in the secondembodiment. Moreover, the display instrument of the present invention isequivalent to, for example, the white color component detectioninstrument 207, white display element driving instrument 208, whitedisplay unit 209, RGB display element driving instrument 210, and RGBdisplay unit 211 in the second embodiment.

In addition, the R (red) color, G (green) color, and B (blue) color ofthis sixth embodiment are examples of the three primary colors of thepresent invention, the RGB signals of this embodiment are examples ofthe chrominance signals of the present invention, and the yellow of thissixth embodiment is an example of the predetermined color of the presentinvention.

Moreover, although the example of detecting whether a pastel yellowpixel is a part of a checkered pattern is described in this embodiment,it is not limited to this similarly to the fifth embodiment, but it maybe sufficient to detect whether it is a part of another pattern.

Furthermore, although the example of performing frame alternation asfirst switching signal generation instrument is described in thisembodiment, it is also applicable to a case of not performing the framealternation, similarly to the fifth embodiment.

In addition, although it is described in this sixth embodiment that RGBsignals are inputted into the display apparatus 260, it is not limitedto this, but signals of expressing colors other than the RGB signals maybe inputted.

Furthermore, although the display apparatus 260 performed theprocessing, which decreased the sense of incongruity of yellowappearance, in this sixth embodiment, it is also possible to perform theprocessing which decreases the sense of incongruity of magenta or cyan.

In addition, although the conversion which the first signal levelconversion processing instrument 202 gave to a blue signal was linearconversion at a predetermined intensity level or higher as shown in FIG.2(a) in this sixth embodiment, nonlinear conversion is acceptable. Inshort, the first signal level conversion processing instrument 202 hasonly to convert the B signal inputted into the first signal levelconversion processing instrument 202 so as to be a small value incomparison with the B signal at the time of an input.

Furthermore, in this sixth embodiment, although the conversion whichsecond signal level conversion processing instrument 203 gave to theblue signal was linear conversion up to the predetermined intensitylevel, it may be nonlinear conversion. In short, the second signal levelconversion processing instrument 203 has only to convert the B signalinputted into the first signal level conversion processing instrument202 so as to be a large value in comparison with the B signal at thetime of the input.

In the fifth embodiment, even if a bright yellow (yellow with lowsaturation), that is, pastel yellow display portion being surrounded bywhite or being adjacent to white, it was possible to decrease the senseof incongruity that visible color appears differently such as the pastelyellow display portion seeming greenish and the like when a displayportion did not fulfill a predetermined condition.

In the sixth embodiment, even if a bright yellow (yellow with lowsaturation), that is, pastel yellow display portion being surrounded bywhite or being adjacent to white, it was possible to decrease the senseof incongruity that visible color appears differently such as the pastelyellow display portion seeming greenish and the like and further, toobtain the same effect by changing the processing even when the displayportion did not fulfill a predetermined condition.

Embodiment 7

Hereafter, a seventh embodiment will be described. Although thefundamental structure of a display apparatus of this seventh embodimentis the same as the fifth embodiment, a predetermined condition differsfrom that of the fifth embodiment. Therefore, description will beperformed with focusing on this difference.

In this seventh embodiment, as a predetermined condition, it is made acondition that a plurality of pixels where chrominance signals includinga yellow color component are displayed is not spatially displayedadjacently. This predetermined condition is equivalent to an example ofthe predetermined condition of the present invention.

The pixel 248 in FIG. 22 is mentioned as an example, and patterndetection will be described below.

Firstly, it is detected about the pixel 248 and pixel 249 whether|R1-R2|<Threshold 1, |G1-G2|<Threshold 1, and |B1-B2|<Threshold 1 arefulfilled. When result is true, this means that colors of the pixel 248and pixel 249 are similar and means that two or more are adjacent, andhence, the pattern detection is ended and “1” is outputted to thearithmetic unit 214 since the predetermined condition is not fulfilled.

When being false, it is detected about the pixel 248 and pixel 251whether |R1-R4|<Threshold 1, |G1-G4|<Threshold 1, and |B1-B4|<Threshold1 are fulfilled. When result is true, this means that colors of thepixel 248 and pixel 251 are similar and means that two or more areadjacent, and hence, the pattern detection is ended and “1” is outputtedto the arithmetic unit 214 since the predetermined condition is notfulfilled.

Moreover, when being false, it is detected whether colors of the pixel249, and pixel 250 or pixel 252 which are horizontally adjacent to thepixel 248 are similar. Thus, the detection is performed one by onehorizontally, about the pixel of the first line, and is moved to thenext line when all of the detection results are false, and the detectionis performed similarly to the above. Then, when truth is detected, thepattern detection is ended and “1” is outputted to the arithmetic unit214. Furthermore, when being false even if the pattern detection aboutall the chrominance signals displayed in a display region is performed,“0” is outputted to the arithmetic unit 214.

When the pattern detection is performed as mentioned above, the displayapparatus 212 displays the yellow pixels 236 and white pixels 237 inturn spatially, and displays the chrominance signals, which do notinclude the predetermined color component, as it is, in a state thatassumes that all the chrominance signals displayed on a predetermineddisplay region include the yellow color component. At this time, theyellow pixels 236 and white pixels 237 may be also displayed every twoor more pixels as shown in the display region 239 of FIG. 19. Displayingin this way is equivalent to an example of the control of the presentinvention.

In addition, although the yellow pixels 236 and white pixels 237 weredisplayed in turn in the state that it was assumed that all thechrominance signals displayed on a predetermined display region includedthe yellow color component since the first B signal and second B signalwere selected every pixel display, the first B signal and second Bsignal may be switched every display to a pixel of chrominance signalswhere the yellow color component is detected by the color componentseparation and detection instrument 1. In this case, as for thechrominance signals displayed on the display region 266 of FIG. 27, theyellow pixels 236 and white pixels 237 are displayed in turn only everyplural pixels, which are adjacent, like the display region 267, withoutall including the yellow color component. Displaying in this way is alsoequivalent to an example of the control of the present invention.

In addition, the program of the present invention is a program forexecuting functions of all or a part of instrument of the displayapparatus of the present invention mentioned above by a computer, and isa program which operates with collaborating with the computer.

Moreover, the recording medium of the present invention is a recordingmedium which records a program for executing functions of all or a partof instrument of the display apparatus of the present invention,mentioned above, by a computer, and is a recording medium for theabove-mentioned program being readable by a computer and executing theabove-mentioned functions with collaborating with the above-mentionedcomputer.

In addition, the above-mentioned “a part of instrument” of the presentinvention means one or some instrument of a plurality of instrument.

Moreover, the above-mentioned “functions of instrument” of the presentinvention means functions of all or a part of the above-mentionedinstrument.

Furthermore, the program of the present invention is a program forexecuting the operation of all or a part of steps of the display methodof the present invention, as mentioned above, by a computer, and is aprogram which operates with collaborating with the computer.

Moreover, the recording medium of the present invention is a recordingmedium which records a program for executing all or a part of operationof all or a part of steps of the display method of the presentinvention, mentioned above, by a computer, and is a recording medium forthe above-mentioned program being readable by a computer and executingthe above-mentioned operation with collaborating with theabove-mentioned computer.

In addition, the above-mentioned “a part of steps” of the presentinvention means one or some of a plurality of steps.

Moreover, the above-mentioned “operation of steps” of the presentinvention means the operation of all or a part of the above-mentionedsteps.

In addition, one utilizing form of the program of the present inventionmay be an aspect of being recorded on a recording medium which can beread by a computer, and operating with collaborating with the computer.

Moreover, one utilizing form of the program of the present invention maybe an aspect of being transmitted inside a transmission medium, beingread by a computer, and operating with collaborating with the computer.

Furthermore, as a recording medium, ROM and the like are included, andas transmission media, transmission media such as the Internet, light,radio waves, and acoustic waves are included.

In addition, the computers of the present invention which is mentionedabove may be not only pure hardware such as a CPU, but also firmware, anOS, and what includes a peripheral device.

Furthermore, as described above, the structure of the present inventionmay be realized not only by software, but also by hardware.

The display apparatus, display method, program, and recording mediumaccording to the present invention are useful to a display apparatus, adisplay method, a program, and a recording medium for having an effectthat the sense of incongruity of the visual aspect of color decreases,making one pixel displayable in four colors, that is, three primarycolors and a white color, and inputting and displaying chrominancesignals corresponding to a mixing ratio of the above-mentioned fourcolors.

1-9. (canceled)
 10. A display apparatus which makes one pixeldisplayable in four colors, that is, three primary colors and a whitecolor, and inputs and displays chrominance signals corresponding to amixing ratio of said four colors, comprising: color correctioninstrument which performs a first color correction of increasing thesaturation of said chrominance signals and a second color correction ofincreasing a white color component of said chrominance signals, when apredetermined color component exists in said chrominance signalscorresponding to said pixel; selection instrument which switchestemporally a first-chrominance signal obtained by said first colorcorrection, and a second chrominance signal obtained by said secondcolor correction, and selects either; and display instrument whichdisplays the chrominance signal, which is selected, in said pixel.
 11. Adisplay apparatus which makes one pixel displayable in four colors, thatis, three primary colors and a white color, inputs chrominance signalscorresponding to a mixing ratio of said four colors, and displays themwithout decreasing the number of colors, comprising: color correctioninstrument which performs a first color correction of increasingsaturation of said chrominance signals and a second color correction ofincreasing a white color component of said chrominance signals, when apredetermined color component exists in said chrominance signalscorresponding to said pixel; height generation instrument which gives,when there is a region where a plurality of pixels having saidpredetermined color component exist adjacently, at least heightdifference in saturation to said region by selecting either of saidfirst chrominance signals and said second chrominance signals for everypixel of said region according to a predetermined pattern for selectingsaid first chrominance signals obtained by said first color correction,and said second chrominance signals obtained by said second colorcorrection in turn for every one pixel or a plurality of adjacentpixels; and display instrument which displays said region where at leastsaid height difference in saturation is given.
 12. The display apparatusaccording to claim 10, wherein said predetermined color is yellow,magenta, or cyan.
 13. The display apparatus according to claim 11,wherein said predetermined color is yellow, magenta, or cyan.
 14. Thedisplay apparatus according to claim 10, wherein said three primarycolors are red, green, and blue.
 15. The display apparatus according toclaim 11, wherein said three primary colors are red, green, and blue.16. The display apparatus according to claim 10, wherein saidchrominance signals are RGB signals.
 17. The display apparatus accordingto claim 16, wherein, when said predetermined color is yellow, saidcolor correction instrument performs said first color correction bydecreasing a value of a B signal of said chrominance signals andperforms said second color correction by increasing a B signal of saidchrominance signals, when a yellow color component exists in saidchrominance signals corresponding to said pixel.
 18. The displayapparatus according to claim 11, wherein said chrominance signals areRGB signals.
 19. The display apparatus according to claim 18, wherein,when said predetermined color is yellow, said color correctioninstrument performs said first color correction by decreasing a value ofa B signal of said chrominance signals and performs said second colorcorrection by increasing a B signal of said chrominance signals, when ayellow color component exists in said chrominance signals correspondingto said pixel.
 20. The display apparatus according to claim 10 whereinsaid selection instrument switches temporally and selects either saidfirst chrominance signal or said second chrominance signal using asignal of determining the timing when said display instrument performsdisplay in said pixel.
 21. The display apparatus according to claim 11,wherein said height generation instrument performs the selection of saidfirst chrominance signals and said second chrominance signals using asignal of determining timing when said display instrument performsdisplay in said pixel.
 22. A display method of making one pixeldisplayable in four colors, that is, three primary colors and a whitecolor, and inputting and displaying chrominance signals corresponding toa mixing ratio of said four colors, comprising: a color correction stepof performing a first color correction of increasing the saturation ofsaid chrominance signals and a second color correction of increasing awhite color component of said chrominance signals, when a predeterminedcolor component exists in said chrominance signals corresponding to saidpixel; a selection step of switching temporally a first chrominancesignal obtained by said first color correction, and a second chrominancesignal obtained by said second color correction, and selecting either;and a display step of displaying the chrominance signal, which isselected, in said pixel.
 23. A display method of making one pixeldisplayable in four colors, that is, three primary colors and a whitecolor, and inputting chrominance signals corresponding to a mixing ratioof said four colors, and displaying them without decreasing the numberof colors, comprising: a color correction step of performing a firstcolor correction of increasing saturation of said chrominance signalsand a second color correction of increasing a white color component ofsaid chrominance signals, when a predetermined color component exists insaid chrominance signals corresponding to said pixel; a heightgeneration step of giving, when there is a region where a plurality ofpixels having said predetermined color component exist adjacently, atleast height difference in saturation to said region by selecting eitherof said first chrominance signals and said second chrominance signalsfor every pixel of said region according to a predetermined pattern forselecting said first chrominance signals obtained by said first colorcorrection, and said second chrominance signals obtained by said secondcolor correction in turn for every one pixel or a plurality of adjacentpixels; and a display step of displaying said region where at least theheight difference in saturation is given.
 24. A recording medium whichbears a program for making a computer function as color correctioninstrument which performs the first color correction of increasing thesaturation of said chrominance signals and the second color correctionof increasing a white color component of said chrominance signals, whena predetermined color component exists in said chrominance signalscorresponding to said pixel, and selection instrument which switchestemporally a first chrominance signal obtained by said first colorcorrection, and a second chrominance signal obtained by said secondcolor correction, and selects either, in the display apparatus accordingto claim 10, and the recording medium can be processed by a computer.25. A recording medium which bears a program for making a computerfunction as: color correction instrument which performs a first colorcorrection of increasing saturation of said chrominance signals and asecond color correction of increasing a white color component of saidchrominance signals, when a predetermined color component exists in saidchrominance signals corresponding to said pixel; and height generationinstrument which gives, when there is a region where a plurality ofpixels having said predetermined color component exist adjacently, atleast height difference in saturation to said region by selecting eitherof said first chrominance signals and said second chrominance signalsfor every pixel of said region according to a predetermined pattern forselecting said first chrominance signals obtained by said first colorcorrection, and said second chrominance signals obtained by said secondcolor correction in turn for every one pixel or a plurality of adjacentpixels, in the display apparatus according to claim 11, and therecording medium can be processed by a computer.
 26. A display apparatuswhich makes one pixel displayable in four colors, that is, three primarycolors and a white color, and inputs and displays chrominance signalscorresponding to a mixing ratio of said four colors, comprising: colordetection instrument which detects whether a predetermined colorcomponent is included in each chrominance signal corresponding to eachpixel in a predetermined region; color correction instrument whichperforms a first color correction of increasing the saturation of saidchrominance signals and creating a first chrominance signal, and asecond color correction of increasing a white color component of saidchrominance signals and creating a second chrominance signal, controlinstrument which performs the color correction of a chrominance signal,including said predetermined color component, by said color correctioninstrument, and performs control so that said first chrominance signaland said second chrominance signal may be displayed spatially in turn inevery predetermined plural pixel units, which are horizontally and/orvertically adjacent, in said predetermined region; and displayinstrument which displays said first chrominance signal, said secondchrominance signal, or a chrominance signal, which is not given saidcolor correction, in said pixel on the basis of said control instrument.27. The display apparatus according to claim 26 wherein said everypredetermined plural pixel units is every two pixel units.
 28. Thedisplay apparatus according to claim 26, wherein in the case that saidcontrol instrument performs control so that said first chrominancesignal and said second chrominance signal may be displayed spatially inturn in every predetermined plural pixel units, which are horizontallyadjacent, in said predetermined region, said control instrument switchesand selects said first chrominance signal and said second chrominancesignal in every said predetermined plurality of dot clock signals fordetermining display timing of every pixel in said predetermined region.29. The display apparatus according to claim 26, wherein in the casethat said control instrument performs control so that said firstchrominance signal and said second chrominance signal may be displayedspatially in turn in every predetermined plural pixel unit, which arevertically adjacent, in said predetermined region, said controlinstrument switches and selects said first chrominance signal and saidsecond chrominance signal for every said predetermined plurality ofhorizontal periods in said predetermined region.
 30. The displayapparatus according to claim 26 wherein said control instrument performscontrol so that said first chrominance signal and said secondchrominance signal may be displayed in a pixel of said predeterminedregion in turn temporally.
 31. The display apparatus according to claim26, wherein said control instrument performs control so that achrominance signal which does not include said color component may bedisplayed without performing said color correction, and performs controlso as to be displayed in turn spatially, where it is assumed that allthe chrominance signals displayed in a pixel of said predeterminedregion include said predetermined color component.
 32. The displayapparatus according to claim 26, wherein said predetermined colorcomponent is yellow, magenta, or cyan.
 33. The display apparatusaccording to claim 26, wherein said three primary colors are red, green,and blue.
 34. The display apparatus according to claim 26, wherein saidchrominance signals are RGB signals.
 35. The display apparatus accordingto claim 26, wherein, when said predetermined color component is yellow,said color correction instrument performs said first color correction bydecreasing a value of a B signal of said chrominance signal and performssaid second color correction by increasing a value of the B signal ofsaid chrominance signal, when a yellow color component exists in saidchrominance signals corresponding to said pixel.
 36. A display methodusing a display apparatus which makes one pixel displayable in fourcolors, that is, three primary colors and a white color, and inputs anddisplays chrominance signals corresponding to a mixing ratio of saidfour colors, comprising: a color detection step of detecting whether apredetermined color component is included in each chrominance signalcorresponding to each pixel in a predetermined region; a colorcorrection step of performing a first color correction of increasing thesaturation of said chrominance signals and creating said firstchrominance signal, and a second color correction of increasing a whitecolor component of said chrominance signals and creating a secondchrominance signal, a control step of performing said color correctionof a chrominance signal, including said predetermined color component,and performing control so that said first chrominance signal and saidsecond chrominance signal may be displayed spatially in turn in everypredetermined plural pixel units, which are horizontally and/orvertically adjacent, in said predetermined region; and a display step ofdisplaying said first chrominance signal, said second chrominancesignal, or a chrominance signal which is not given said colorcorrection, in said pixel on the basis of said control.
 37. A recordingmedium which records a program for making a computer execute: a colordetection step of detecting whether a predetermined color component isincluded in each chrominance signal corresponding to each pixel in apredetermined region; a color correction step of performing a firstcolor correction of increasing the saturation of said chrominancesignals and creating a first chrominance signal, and a second colorcorrection of increasing a white color component of said chrominancesignals and creating a second chrominance signal; and a control step ofperforming said color correction of a chrominance signal, including saidpredetermined color component, and performing control so that said firstchrominance signal and said second chrominance signal may be displayedspatially in turn in every predetermined plural pixel units, which arehorizontally and/or vertically adjacent, in said predetermined region,of the display method according to claim 36, and the recording mediumcan be processed by a computer.
 38. A display apparatus which makes onepixel displayable in four colors, that is, three primary colors and awhite color, and inputs and displays chrominance signals correspondingto a mixing ratio of said four colors, comprising: color detectioninstrument which detects whether a predetermined color component isincluded in each chrominance signal corresponding to each pixel in apredetermined region; color correction instrument which performs a firstcolor correction of increasing the saturation of said chrominancesignals and creating a first chrominance signal, and a second colorcorrection of increasing a white color component of said chrominancesignals and creating a second chrominance signal; judgment instrumentwhich judges whether a plurality of chrominance signals displayed in apixel of said predetermined region fulfills a predetermined condition;control instrument which performs the color correction of chrominancesignals including said predetermined color component by said colorcorrection instrument when not fulfilling said predetermined condition;and display instrument which displays said first chrominance signal,said second chrominance signal, or a chrominance signal which is notgiven said color correction, in a pixel of said predetermined region onthe basis of said control instrument.
 39. The display apparatusaccording to claim 38, wherein said predetermined condition is acondition that chrominance signals including, said predetermined colorcomponent, are not displayed in two or more adjoining pixels spatially.40. The display apparatus according to claim 38, wherein saidpredetermined condition is a condition that when a chrominance signalwhich does not include said color component is displayed withoutperforming said color correction, and about the chrominance signalsincluding said color component, said first chrominance signal and saidsecond chrominance signal are displayed in turn spatially in a statethat assumes that all the chrominance signals displayed in a pixel ofsaid predetermined region include the predetermined color component and,either of an area where said first chrominance signal is displayed, andan area where said second chrominance signal is displayed is larger by5% or more than the other.
 41. The display apparatus according to claim38, wherein said predetermined condition is a condition that, when achrominance signal which does not include said color component isdisplayed without performing said color correction, and concerning achrominance signals which include said color component, said firstchrominance signal and said second chrominance signal are displayed inturn spatially in a state that assumes that all the chrominance signalsdisplayed in a pixel of said predetermined region include thepredetermined color component, either said first chrominance signal orsaid second chrominance signal is displayed except a chrominance signalwhich is not given said color correction.
 42. The display apparatusaccording to claim 39, wherein, when said predetermined condition is notfulfilled, said control instrument performs control so that said firstchrominance signal and said second chrominance signal may be displayedin turn spatially in every pixel unit or in every plural pixel units insaid predetermined region.
 43. The display apparatus according to claim40, wherein, when said predetermined condition is not fulfilled, saidcontrol instrument performs control so that said first chrominancesignal and said second chrominance signal may be displayed in turnspatially in every pixel unit in said predetermined region in a statethat assumes that all the chrominance signals displayed in a pixel ofsaid predetermined region include the predetermined color component. 44.The display apparatus according to claim 41, wherein, when saidpredetermined condition is not fulfilled, said control instrumentperforms control so that said first chrominance signal and said secondchrominance signal may be displayed in turn spatially in every pixelunit in said predetermined region in a state that assumes that all thechrominance signals displayed in a pixel of said predetermined regioninclude the predetermined color component.
 45. The display apparatusaccording to claim 43, wherein, when said predetermined condition isfulfilled, said control instrument performs control so that concerning achrominance signal which does not include said color component, saidcontrol instrument does not perform said color correction, andconcerning the chrominance signals which include said color component,said first chrominance signal and said second chrominance signal may bedisplayed in turn spatially in every plural pixel units in saidpredetermined region in a state that assumes that all the chrominancesignals displayed in a pixel of said predetermined region include thepredetermined color component.
 46. The display apparatus according toclaim 44, wherein, when said predetermined condition is fulfilled, saidcontrol instrument performs control so that concerning a chrominancesignal which does not include said color component, said controlinstrument does not perform said color correction, and concerning thechrominance signals which include said color component, said firstchrominance signal and said second chrominance signal may be displayedin turn spatially in every plural pixel units in said predeterminedregion in a state that assumes that all the chrominance signalsdisplayed in a pixel of said predetermined region include thepredetermined color component.
 47. The display apparatus according toclaim 42, wherein said control instrument has switching signalgenerating instrument which generates such a switching signal that saidfirst chrominance signal and said second chrominance signal may bedisplayed in turn in every pixel unit or in every plural pixel units,and wherein performing control so as to be displayed in turn spatiallyis selecting said first chrominance signal and said second chrominancesignal in turn on the basis of said switching signal.
 48. The displayapparatus according to claim 43, wherein the control instrument hasswitching signal generating instrument which generates such a switchingsignal that said first chrominance signal and said second chrominancesignal may be displayed in turn in every pixel unit, and whereinperforming control so as to be displayed in turn spatially is selectingsaid first chrominance signal and said second chrominance signal in turnon the basis of said switching signal, in a state that assumes that allthe chrominance signals displayed in a pixel of said predeterminedregion include the predetermined color component.
 49. The displayapparatus according to claim 44, wherein the control instrument hasswitching signal generating instrument which generates such a switchingsignal that said first chrominance signal and said second chrominancesignal may be displayed in turn in every pixel unit, and whereinperforming control so as to be displayed in turn spatially is selectingsaid first chrominance signal and said second chrominance signal in turnon the basis of said switching signal, in a state that assumes that allthe chrominance signals displayed in a pixel of said predeterminedregion include the predetermined color component.
 50. The displayapparatus according to claim 45, wherein said control instrument has:first switching signal generating instrument which generates a firstswitching signal so that said first chrominance signal and said secondchrominance signal may be displayed in turn in every pixel unit in apixel of a predetermined region; second switching signal generatinginstrument which generates a second switching signal so that said firstchrominance signal and said second chrominance signal may be displayedin turn in every plural pixel units in a pixel of a predeterminedregion; and switching signal selection instrument which selects saidfirst switching signal when said predetermined condition is notfulfilled, and selects said second switching signal when saidpredetermined condition is fulfilled, and wherein performing control soas to be displayed in turn spatially is selecting said first chrominancesignal and said second chrominance signal in turn on the basis of saidfirst switching signal or said second switching signal, in a state thatassumes that all the chrominance signals displayed in a pixel of saidpredetermined region include the predetermined color component.
 51. Thedisplay apparatus according to claim 46, wherein said control instrumenthas: first switching signal generating instrument which generates afirst switching signal so that said first chrominance signal and saidsecond chrominance signal may be displayed in turn in every pixel unitin a pixel of a predetermined region; second switching signal generatinginstrument which generates a second switching signal so that said firstchrominance signal and said second chrominance signal may be displayedin turn in every plural pixel units in a pixel of a predeterminedregion; and switching signal selection instrument which selects saidfirst switching signal when said predetermined condition is notfulfilled, and selects said second switching signal when saidpredetermined condition is fulfilled, and wherein performing control soas to be displayed in turn spatially is selecting said first chrominancesignal and said second chrominance signal in turn on the basis of saidfirst switching signal or said second switching signal, in a state thatassumes that all the chrominance signals displayed in a pixel of saidpredetermined region include the predetermined color component.
 52. Thedisplay apparatus according to claim 47, wherein said switching signalis a signal using a signal which determines the timing of said displayinstrument which displays in said pixel.
 53. The display apparatusaccording to claim 48, wherein said switching signal is a signal using asignal which determines the timing of said display instrument whichdisplays in said pixel.
 54. The display apparatus according to claim 49,wherein said switching signal is a signal using a signal whichdetermines the timing of said display instrument which displays in saidpixel.
 55. The display apparatus according to claim 50, wherein saidfirst switching signal and said second switching signal are signalsusing a signal which determines the timing of said display instrumentwhich displays in said pixel.
 56. The display apparatus according toclaim 51, wherein said first switching signal and said second switchingsignal are signals using a signal which determines the timing of saiddisplay instrument which displays in said pixel.
 57. The displayapparatus according to claim 38, wherein said control instrumentperforms control so that said first chrominance signal and saidsecond-chrominance signal are displayed in a pixel of said predeterminedregion in turn temporally.
 58. The display apparatus according to claim38, wherein the color around said predetermined region is white.
 59. Thedisplay apparatus according to claim 38, wherein said predeterminedcolor component is yellow, magenta, or cyan.
 60. The display apparatusaccording to claim 38, wherein said three primary colors are red, green,and blue.
 61. The e display apparatus according to claim 38, whereinsaid chrominance signals are RGB signals.
 62. The display apparatusaccording to claim 61, wherein said predetermined color component isyellow; and wherein said color correction instrument performs said firstcolor correction by decreasing a value of a B signal of said chrominancesignals, and performs said second color correction by increasing a valueof the B signal of said chrominance signals.
 63. A display method usinga display apparatus which makes one pixel displayable in four colors,that is, three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising: a color detection step of detecting whether a predeterminedcolor component is included in each chrominance signal corresponding toeach pixel in a predetermined region; a color correction step ofperforming a first color correction of increasing the saturation of saidchrominance signals and creating a first chrominance signal, and asecond color correction of increasing a white color component of saidchrominance signals and creating a second chrominance signal; a judgmentstep of judging whether a plurality of chrominance signals displayed ina pixel of said predetermined region fulfill a predetermined condition;a control step of performing control so as to perform the colorcorrection of chrominance signals including said predetermined colorcomponent when not fulfilling said predetermined condition; and adisplay step of displaying said first chrominance signal, said secondchrominance signal, or a chrominance signal which is not given saidcolor correction, in a pixel of said predetermined region on the basisof said control.
 64. A recording medium which records a program formaking a computer execute: the color detection step of detecting whethera predetermined color component is included in each chrominance signalcorresponding to each pixel in said predetermined region; the colorcorrection step of performing the first color correction of increasingthe saturation of said chrominance signals and creating a firstchrominance signal, and the second color correction of increasing awhite color component of said chrominance signals and creating a secondchrominance signal; the judgment step of judging whether a plurality ofchrominance signals displayed in a pixel of said predetermined regionfulfill a predetermined condition; and the control step of performingcontrol so as to perform said color correction of chrominance signalsincluding said predetermined color component when not fulfilling saidpredetermined condition, of the display method according to claim 63,and the recording medium can be processed by a computer.
 65. A displayapparatus which makes one pixel displayable in four colors, that is,three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising: color detection instrument which detects whether apredetermined color component is included in each chrominance signalcorresponding to each pixel in a predetermined region; judgmentinstrument which judges whether a plurality of chrominance signalsdisplayed in a pixel of said predetermined region fulfill apredetermined condition; color correction instrument which performs thefirst color correction of increasing the saturation of saidpredetermined chrominance component of said chrominance signals andcreating a first chrominance signal, and the second color correction ofincreasing a white color component of said chrominance signals andcreating a second chrominance signal; switching signal generatinginstrument which generates such a switching signal that said firstchrominance signal and said second chrominance signal may be displayedin turn in every one or in plural pixel units, in a state that assumesthat all the chrominance signals displayed on a pixel of saidpredetermined region include said predetermined color component; firstselection instrument which selects said first chrominance signal or saidsecond chrominance signal in turn on the basis of said switching signal,in a state that assumes that all the chrominance signals displayed on apixel of said predetermined region include the predetermined colorcomponent; second selection instrument which selects said firstchrominance signal or said second chrominance signal when saidpredetermined color component is included and said predeterminedcondition is not fulfilled, and otherwise selects a chrominance signalwhich is not given said color correction; and display instrument whichdisplays said first chrominance signal, said second chrominance signal,or a chrominance signal not given said color correction, which isselected by said first selection instrument and said second selectioninstrument, in a pixel of said predetermined region.
 66. A displayapparatus which makes one pixel displayable in four colors, that is,three primary colors and a white color, and inputs and displayschrominance signals corresponding to a mixing ratio of said four colors,comprising: color detection instrument which detects whether apredetermined color component is included in each chrominance signalcorresponding to each pixel in a predetermined region; judgmentinstrument which judges whether a plurality of chrominance signalsdisplayed in a pixel of said predetermined region fulfill apredetermined condition; color correction instrument which performs afirst color correction of increasing the saturation of saidpredetermined chrominance component of said chrominance signals andcreating a first chrominance signal, and a second color correction ofincreasing a white color component of said chrominance signals andcreating a second chrominance signal; first switching signal generatinginstrument which generates a first switching signal so that said firstchrominance signal and said second chrominance signal may be displayedin turn in every pixel unit, in a state that assumes that all thechrominance signals displayed on a pixel of said predetermined regioninclude said predetermined color component; second switching signalgenerating instrument which generates a second switching signal so thatsaid first chrominance signal and said second chrominance signal may bedisplayed in turn in every plural pixel units, in a state that assumesthat all the chrominance signals displayed on a pixel of saidpredetermined region include said predetermined color component;switching signal selection instrument which selects said first switchingsignal when said predetermined condition is not fulfilled, and selectssaid second switching signal when said predetermined condition isfulfilled; first selection instrument which selects said firstchrominance signal or said second chrominance signal on the basis ofsaid first switching signal or said second switching signal which isselected by said switching signal selection instrument; second selectioninstrument which selects said first chrominance signal or said secondchrominance signal, which is selected by said first selectioninstrument, when said predetermined color component is included, andselects a chrominance signal, which is not given said color correction,when said predetermined color component is not included; and displayinstrument which displays said first chrominance signal, said secondchrominance signal, or a chrominance signal not given said colorcorrection, which is selected by said first selection instrument andsaid second selection instrument, in a pixel of the predeterminedregion.